"I'd like to make a suggestion."
Having gathered everyone in the recreation room again, Kamo drank some coffee to wake himself up. He began his speech as soon as he finished.
Since his smartphone had gone dead and he didn't wear a watch, he checked the clock on the wall for the time. It was so dark outside, it was hard to believe it was only 4:30 P.M. It was probably because of the heavy rain clouds.
"We're dealing with a very crafty culprit. Even if you lock yourselves in your rooms, there's no guarantee that it will protect you."
Tsukihiko laughed mockingly. He took a sip of milk tea before responding.
"We know that even if you don't say so. It seems impossible crimes are a fact of life in this villa."
He said that as though it were someone else's problem, but his bloodshot eyes exposed his concern. He licked his lips before continuing.
"So you all can just kick back and relax, right? According to the detective's reasoning... the only people left on the culprit's list are Dad and I, the two remaining pieces of the Nue."
Soujirou dropped his teacup, spilling the reddish liquid across the table. He stared at Kamo as though he hadn't even noticed.
"Isn't there anything we can do?"
Amamiya and Tsukie got up and went to the dining room to get a dish towel. Kamo glanced sideways at them as he continued.
"This is a common proposal in closed circles, but... the only option is for everyone to gather together and keep watch on each other all night."
Soujirou's face twitched.
"We can't just do something so passive! Do you really think you'll be able to protect us like that? We don't know what sort of tricks the culprit has set up in the villa!"
"If you don't feel comfortable with a room in the building, we can always use the wood chopping shed or the camping trailer. The important bit is that we have to monitor each other's movements."
"The wood chopping shed or the camping trailer?"
Internally, Kamo panicked. Amamiya had muttered with the dish towel still in his hands and an indescribable expression.
"I'm sorry for saying things without thinking. Is there perhaps a reason why we shouldn't gather there?"
Amamiya's face immediately turned apologetic.
"I'm sorry, it's just... the wood chopping shed is full of gaps, so I don't think it will be usable in this rain... on the other hand, even though it's small, I think the camping trailer is usable. The Master brought it from overseas because it was a rare find. It's sturdier than it looks, and we keep it in good condition, so we can use it at any time."
Soujirou cut him off, apparently not liking the direction their talk was going.
"It's not a matter of location. Have you forgotten that the culprit has hidden a hunting rifle somewhere? If they were to take aim at us while we were unarmed, they could easily kill all seven of us."
Kamo spoke slowly in what he hoped was a calming tone.
"If we search everyone, they won't be able to bring the gun with them. It will be fine."
"That's useless, the enemy has already committed multiple impossible crimes. I'm sure they could come up with plenty of ways... and let's not forget that 24 bullets have gone missing. The culprit would have three shots for each of us."
Three bullets for a person was the textbook definition of "excessive force". Seeing that Kamo had gone silent, Tsukihiko decided to speak up.
"For the time being, nobody disagrees with the claim that Dad and I are the ones in danger, correct? In that case... Dad and I are the ones who have the right to decide how we spend the evening. You all are just spectators, but we're the ones who are being forced to risk our lives."
An awkward silence ensued. It was only interrupted when Tsukie brought Soujirou a new cup of lemon tea.
That made Kamo remember that Amamiya and Tsukie, who were acting as waiters for the group, hadn't asked anyone other than him what they wanted to drink. It seemed Soujirou and Tsukihiko always took tea, Ayaka drank cocoa, and everyone else took coffee.
Tsukie placed the teacup in front of Soujirou, then asked her brother:
"So what do you propose?"
"I don't want to spend the night in the same room as a murderer. I'd rather lay an ambush in my room."
"You say that, but Mr. Taiga may have been attacked by the culprit within his own room. Even if you hole up in the Snake Room, that doesn't necessarily mean you're safe."
Tsukihiko didn't seem the least bit worried. He answered Kamo's concerns with a smile.
"I know that much. I can take care of myself."
From Kamo's perspective, that sounded an awful lot like a death flag, but Soujirou didn't seem to think so as he timidly interjected.
"I also don't have the nerve to spend the night in the same room as everyone else. I wouldn't want the culprit to attack while I was sleeping."
Although this was a predictable development, Kamo had hoped it could be avoided if at all possible. He sighed.
"I won't force anyone to do anything... In that case, I'd like to gather everyone who does agree with my proposal to spend the night together."
"Now, who's actually going to listen to you?" Tsukihiko asked.
Ayaka looked up from sipping her cocoa with an annoyed expression.
"I'll follow Mr. Kamo's suggestion."
"Then so will I."
Genji was the next. Seeing the way Tsukihiko's eyebrows shot up, he gave a wry smile.
"After all, this girl's only in middle school. I've been worried about whether she can be left alone like this for a while now. If Ayaka wants to do it, then I will too... Besides, I think there's something to Mr. Kamo's idea."
"You mean you're actually listening to this pathetic detective?"
"Certainly, if we want to protect you and Soujirou, it's best to gather everyone else together. That way, we can keep eyes on each other and make sure nobody has a chance to commit any crimes."
Hearing his argument, Amamiya, who had previously looked hesitant, nodded with relief.
"I agree with Mr. Genji."
After looking at Amamiya with cold eyes, Tsukihiko turned to look at his sister next to him.
"And then there were four. Well then, we'll-"
"Brother, I will also follow Mr. Kamo."
Tsukie spoke without even looking at her brother. Tsukihiko recoiled in shock.
"What are you saying? Are you going against me?" he screamed, slamming his teacup on the table. The sharp sound made Tsukie flinch, but she quickly shook her head.
"No. I'm doing this for your sake, and Father's, too."
Kamo saw Tsukihiko's fingertips start to move and quickly intervened.
"Then it's decided... I promise, the five of us will all work together until morning and do everything we can to prevent the crime. At the same time, Mr. Soujirou, Mr. Tsukihiko, please do everything you can on your side, too. Please take any measures you can to protect yourself."
Tsukihiko was still fuming at his sister, but he slowly turned his attention back to Kamo.
"So, what's your plan to stop the crime, Detective?"
"We've investigated this building many times, and we can say with certainty that there are no secret rooms or hidden passages. The culprit is either inside the building, or lurking outside. We need to ensure no outsiders can enter the building."
There was already a lock on the back door, but after talking amongst themselves, they decided to take some tables and chairs out of storage and barricade it further. Afterwards, Tsukie, Ayaka, and Soujirou stayed behind in the rec room while Kamo and the others went to the warehouse.
Some of the the chairs in the warehouse were coated in dust, but nobody cared enough to clean them, so they just piled them in front of the back door. As a result, all of the men who'd worked on the barricade were covered in dust. Tsukihiko, who seemed to be a bit of a neat freak, wouldn't stop complaining about how he wanted to take a bath as he rubbed his stubbly chin.
Whatever the case, now the back door couldn't be easily opened, whether from the inside or outside.
As for the front door, while they could have done the same thing, it would be a problem if they ever needed to leave the building, but couldn't... If the culprit were allowed to enter the building, the barricade could delay their own escape.
For the time being, Tsukihiko was given all the keys to the front door and told to lock it from the inside.
However, there was the possibility that the culprit had at some point made a duplicate key to the front door, so that wasn't a foolproof solution.
In the end, Amamiya got a bicycle chain lock from the bike shed and wrapped it around the handles of the double doors as an extra measure. There were spare keys for the chain lock, so Tsukihiko and Soujirou were each given one.
No matter how many precautions they took, there was no way they could stop the culprit from just physically forcing their way in. However, the noise that would make would give them time to prepare to defend themselves or escape.
Next, they prepared countermeasures in the event that the culprit was among the seven of them. As soon as they started talking, Tsukihiko burst out laughing.
"Alright then, I guess the Detective will have to spend the night out in the camping trailer."
Kamo raised an eyebrow.
"I did suggest that earlier, but why should I be the only one to go out there?"
The heavy rain was still pelting the window panes. When Amamiya saw that, he couldn't take it any more and ripped into Tsukihiko.
"Even though the weather's like this... It's not just me, but Mr. Genji, Ms. Tsukie, and the Young Mistress will all be together, right? I'm sure it would be better if we all stayed in the recreation room."
Tsukihiko snorted. From the look of delight on his face, it was clear to Kamo that he'd made the suggestion just to rile him up.
Ever since they'd gotten into the argument over Taiga's guilt, Tsukihiko had been openly hostile towards Amamiya. From the moment Tsukie had announced she was siding with Kamo's proposal, he'd turned the same hostility towards her as well. Apparently, this was Tsukihiko taking a moment for a tasteless revenge.
Tsukihiko turned to his sister, smiled, and spoke in an eerily calm voice.
"I know I'm not the culprit, and I don't think Dad would ever do something so drastic. To be honest, I suspect the culprit is among the five of you. Try putting yourselves in my shoes for a bit... Isn't it only natural to want to put as much distance between the suspects and yourself as possible?"
Giving up on uselessly arguing further, Kamo acquiesced.
"That's fine. If Mr. Soujirou agrees it's necessary, we'll spend the night in the camping trailer."
Soujirou accepted Tsukihiko's proposal, but he looked like he hadn't even heard it. His mind was full of only how to protect himself. He didn't even seem concerned about his own children.
Afterwards, the rain lightened up, and Kamo and Amamiya took the opportunity to go outside and push the camping trailer up about five meters from the villa's front entrance. That would make it easier to see any suspicious figures approaching the front entrance.
Luckily for them, the trailer could be moved with just a few people pushing, as long as they removed the stop first. In the end, the trailer was placed with the entrance facing away from the building.
Amamiya suggested they have dinner, so Kamo dragged his exhausted body to the dining room. The dinner they made while everyone kept an eye on everyone else couldn't be called "a meal", but nobody complained. They forced food they couldn't taste down their throats.
By the time Kamo was finished the coffee he took after dinner to keep himself awake, it was almost 8:00 P.M.
*
It was already dark, but the silver camping trailer still stood out.
It was designed as a simple box, with a single wheeled protrusion from the front. That was probably where it attached to the towing vehicle.
As Kamo checked the jack and the hitch for any abnormalities, Amamiya and Genji, who had gone in ahead of him to check the inside, peeked out. Kamo asked to check Genji's watch. It showed 8:48.
Feeling the wind growing stronger, Kamo called over Ayaka and Tsukie, who were taking shelter from the rain in the bicycle shed. The two of them, holding umbrellas, ran into the trailer, screaming all the way. Genji, perhaps out of concern for the smoke-hating Ayaka, announced he was taking a smoke break and stepped outside.
When Kamo stepped in, he saw Amamiya touching the lantern hanging above the bed.
The lantern spread a soft ersatz sunlight throughout the car. The objects sparkling in that light were a series of bottles brought from the storage room. The once empty bottles of juice and wine now held humble tap water. Each person had washed and filled their own water bottles. That would be their drinking water for the time being.
To put on a finishing touch, Amamiya drew the thick gray curtains and opened a single window. The breeze that came in was so cool it was impossible to believe it was still August.
The trailer was larger than Kamo had pictured from the outside, measuring about 2 meters wide, 4.5 meters long, and 2 meters high. It even had a toilet and kitchen. Kamo could tell it was a foreign-made trailer, because he wasn't sure if it could even fit on a narrow Japanese road.
After ceding the bed to the women, Kamo leaned against the wall near the entrance.
Ayaka took out her pocket watch and wound it before placing it on the bedside table. Next to her, Tsukie began to fix her hair, which was soaking wet. Seeing this, Amamiya took the initiative and opened the cupboard, taking out a towel and handing it to her.
In the meantime, Kamo decided to double check the car's safety. He searched everyone's personal belongings, drawers, and shelves, even checking between the mattress and the bed frame, but he didn't find a single bullet, let alone the gun.
By the time he was finished his investigation, Genji had returned, soaking wet. He'd been gone about five minutes. Kamo searched him, just to be sure. Around then, the wind and rain appeared to be getting stronger, and the trailer occasionally shook.
As Kamo wiped the raindrops off the hourglass with a towel, Amamiya seemed to remember something.
"Ah, I left the umbrellas outside."
He went out to retrieve them because it would be dangerous if one was blown away by a strong wind.
Less than 30 seconds later, lightning struck close by. The deafening roar made Ayaka jump and scream. Kamo became worried about Amamiya and decided to go outside and check on him.
When he opened the door, Amamiya was standing there, soaking wet and holding five umbrellas. Kamo was relieved to see him, but Amamiya stammered in a weak voice.
"I'm not good with thunder..."
When he ran back into the trailer (after being subjected to a body search), Kamo stepped outside and looked up into the sky. Lighting flashed across clouds so dark they were nearly purple, illuminating the fields and road. The light it gave off was so intense he feared for his safety, so he decided to go back in the trailer.
Inside, Amamiya was taking off the leather band of his wristwatch and placing it in the kitchen. Kamo couldn't see the dial, but seeing as how the band was dripping wet, he was probably leaving it to dry.
Kamo tied the trailer's door shut with a rope he'd borrowed from the warehouse to make sure nobody could get out. He then took up position on the steps near the door so he could see any comings and goings. Finally having a chance to catch his breath, he pulled the cork from the wine bottle he had and took a sip. It was only tap water, but... it smelled of wine. It was an unpleasant drink.
As he was about to run out of water, Tsukie suddenly said something.
"What are we going to do until morning? There's no way any of us can sleep."
Genji, who was sitting at the folding table next to the bed, had an idea.
"Why don't we talk about who we suspect? ...You didn't find anything new in today's investigation, did you?"
Those last words were aimed at Kamo. Even though he knew that, he didn't dare answer Genji's question. Instead, he placed the wine bottle at his feet and held the hourglass pendant at his chest.
"I'm sorry, but I'm going to tell them everything... If you have a problem with that, quit sneaking around and show yourself, Hora."
No one but Ayaka knew what he was talking about. In fact, Amamiya looked at him from the kitchen as though he'd lost his mind, and Tsukie gave him a contemptuous glare. On the other hand, Genji, who seemed to have interpreted it as a joke in bad taste, laughed, even though he looked disappointed.
That said, Kamo hadn't been expecting a response from Hora. Rather than asking for a reply, he was just giving an advance notice in case he was eavesdropping from somewhere.
Kamo didn't know where Hora was. In truth, his smartphone had already run out of battery, so even if he wanted to contact Kamo, he couldn't anymore.
Kamo let go of the hourglass and turned to face Genji.
"Come to think of it, I haven't thanked you get, Genji."
"Thanked me?"
A cautious look flashed across Genji's eyes. Kamo continued with a small nod.
"Thanked you for lying that my name sounded familiar. It's thanks to you that I didn't get thrown out of the villa."
Genji looked at Ayaka in confusion. She seemed to understand Kamo's intentions, but she didn't say anything. Genji stiffened.
"...May we interpret that as a confession that you're the murderer?"
"No. I'm not a private investigator, but I'm not a murderer, the one behind this incident or otherwise."
"Then why are you saying all this?"
"I'm just tired of all the lies. Now that I've played my hand, I want to ask you, Genji. Why did you cover for me?"
Kamo had no idea what his words made Genji feel, but his expression softened a bit. Finally, he gave a sigh.
"You're right. I noticed at once that Ayaka was lying."
"Of course you did, her lie was absurd."
"If Ayaka was the sort of girl who told malicious lies, I would have had you detained at once. But she isn't. I understand that better than anyone."
He heard Ayaka murmur "I'm sorry." Just as she was about to continue, Genji interrupted her with a gesture, then spoke in a gentle voice.
"If this girl told a lie, it could only be to make someone happy, or to protect them. That's why I was so confused to see her sticking to her story so stubbornly... At first, I suspected that you had just deceived her. However, you looked like you were as surprised by her story as anyone."
Kamo couldn't help but smile.
"I was suddenly declared a Great Detective. I didn't know what to do... But didn't you ever suspect that I could be the murderer?"
"Not once. There was no way you could have killed my brother or Koki because you were outside the villa, and I didn't think you were an accomplice to anyone on the inside... It was pure coincidence that people had been in the rec room all night, so I didn't think the culprit could have arranged an accomplice to deal with them."
Genji's analysis was astute, but Kamo was unimpressed.
"I see."
"That's not all. You also didn't have any signs of mosquito bites."
That took him by surprise.
"...What do mosquitoes have to do with any of this?"
"As you know, Shino is located at the foot of a mountain. If you spent the night outside at this time of year, you'd have mosquito bites from head to toe."
"I see, I hadn't thought of that."
"That's how I knew you were neither the killer nor an accomplice. That's why I didn't want to see you, an innocent, detained."
Genji let out a huff, and his grin turned mischievous.
"Also, I have a bit of a bad habit. When I get curious about something, I just can't help myself... what Ayaka said was so interesting, I couldn't help but want to see where it would go."
Kamo relaxed. Now he'd seen Genji's true feelings. Genji wiped the metal band of his watch with a towel before continuing.
"However, I wouldn't have shown any mercy if you did anything even slightly suspicious. But I could tell right away that you were serious about solving the case."
Ayaka was giving Genji a silent, pleading stare. He looked straight back at her and continued.
"So, I started thinking like this. I don't know if she had evidence or it was just intuition, but Ayaka had some reason to believe an incident would occur in the villa. But people don't take the words of children seriously, so she couldn't just tell someone. She couldn't just sit back and do nothing, so she decided to invite you to the villa."
"Come to think of it, Ayaka once told me she invited a magician without permission."
When Kamo said that, Genji also gave a small nod.
"Yes, that's why I thought she might have called a private investigator the same way. That's why, until just now, I thought you were a real detective. So, who exactly are you?"
"I'm just a magazine writer. I'm not any sort of professional criminal investigator. But it is true that I came here to prevent incidents that would happen in Shino."
Kamo could feel everyone waiting for his next words. But what he had to say next was something even he thought was too absurd to believe. Kamo could barely be heard as he delivered his next words.
"I knew in advance that a tragedy would happen here. Because I come from the future."
"Yes, Mr. Kamo is from the year 2018."
Hearing Ayaka firmly declare that, the three others exchanged looks. Amamiya's eyes were swimming with agitation, but Genji and Tsukie reacted far less dramatically than he'd expected. If they'd just demanded he stop lying, that would have been much easier.
The first to speak was Amamiya.
"...So you really were."
"Wait, you knew?"
Tsukie giggled.
"We suspected. The way you talk, your glasses, everything about you is different from us, and we were all curious about it."
As Kamo stood speechless, Genji placed his watch, wrapped in a towel, on the bedside table and opened his mouth.
"Your shoes have an interesting design that I've never seen before, not even in science fiction TV shows. I have to admit, it was half as a joke, but I did think you might be from the future."
Kamo felt funny.
"What do you mean, you suspected already? If that's the case, what was the point of us lying all this time?"
Kamo smiled at Ayaka, then explained everything from the beginning. The landslide, the curse of the Ryuuzen clan, Fumino and her descendants, his encounter with Meister Hora, time travel... eventually, he caught up to his arrival in 1960, where Ayaka helped him explain everything they'd done to try and prevent the incidents.
The three of them immediately started asking him about time travel. Kamo was about to explain the four constraints when he was interrupted by a familiar voice.
"It would be for the better if I were to give the explanations, so that there shall be no misunderstandings."
*
Looking for the source of the voice, Kamo realized that it was coming from the hourglass itself. He picked it up with the fingertips of his right hand and saw that it was faintly glowing.
"What, so your eavesdropping device also has a speaker function... where does the battery fit in?"
"There are no batteries here, Kamo."
Hearing Hora's voice, the jaws of the three non-Ayaka onlookers dropped. It seemed they instinctively realized that the voice was genuinely coming from the hourglass. Hora brightened the white light as he spoke.
"It is a pleasure to meet you all. My name is Meister Hora. Allow me to explain to you the nature of travel through time and space."
The hourglass gave them the same lecture it had once given Kamo and Ayaka.
Tsukie and Amamiya were stunned and stood uncomprehending, but Genji, who had earlier stated a familiarity with science fiction, listened with interest. Hora remained glowing all the while, but the hourglass never grew even slightly warm.
When that explanation was over, Kamo asked for another, one that he had wanted for a long time.
So, where are you hiding?"
"I am not hiding anywhere. I've been by your side this whole time."
Kamo blinked several times, then looked around at the four faces he shared the room with. Naturally, Ayaka was among them. All four of them suddenly began to protest that it wasn't them. Hora's laughter echoed throughout the trailer.
"What an amusing misunderstanding. I'm surprised that you mistook me for a human."
Kamo once again looked down at the faintly glowing hourglass.
"Could it be that your true identity is this hourglass... no, this hourglass-shaped time machine?"
"That is correct. I am an artificial intelligence created to manage experiments in time-space travel."
Hearing this, Genji looked down at Hora, an excited gleam in his eye.
"Will time travel technology be developed by 2018? How fascinating."
Kamo shrugged.
"The future I know isn't any sort of sci-fi wonderland. It seems Hora is from a future beyond my own."
Hora's sand turned yellow.
"I was created in a future approximately 290 years after Kamo's era. My creator gave me the shape of an hourglass, the name 'Meister Hora', and a mission."
Hearing this, Ayaka asked suspiciously.
"What was the mission?"
"To determine if the past was changed, and if it had, to set history back on its proper course."
Kamo tilted his head. He found that explanation unsatisfying.
"Is that really possible? If the past is changed, a new future building upon it will be created. Since the old future will disappear, no one will know what it was, will they?"
"If I were a normal space-time device, that would be the case. ...That is why, in order to resolve that problem, my creator made me an existence separate from the world."
Kamo frowned, unable to understand what he'd been told.
"Separate?"
The hourglass you are holding contains no sand. Instead, what you see within is a small world."
Kamo felt a chill and took his hand off the hourglass. Still, the weight on the chain around his neck felt like a pebble. He couldn't believe it was the weight of an entire world.
Hora continued calmly.
"In other words, while I am a time machine, I am also another world, equal to your own. Within my world, there exists a quantum computer, containing the data of my AI and a record of your world, before the past was changed."
"Incredible... an entire different world..."
The contents of Hora's story exceeded anything Kamo could have imagined. Moreover, to Ayaka and the others from 1960, the whole story must have sounded like gibberish. Even so, they appeared to be listening intently to Hora.
"The time flow within me is completely independent. It cannot be altered by any outside force, so no matter what happens in your world... even if history were to be changed, even if my creator were to be killed before I was created, the data within me cannot be rewritten."
"Isn't that more Cassiopeia than Meister Hora?"
Kamo couldn't keep from commenting. In Ende's Momo, Cassiopeia was a tortoise with the ability to move freely, even in a world where time had stopped, because she had her own special time.
Hora replied with a surprising air of nostalgia.
"My creator, Dr. Bastian, gave me the name 'Meister Hora' after the guardian of time and history."
"Whatever the case... that explanation you just gave helped me understand something."
The hourglass gave off a yellow light that seemed to somehow be provoking him.
"Well, what have you discovered?"
"The criminal has done some pretty strange things. First off, even though the presence of people in the rec room all night was a coincidence, they took advantage of it to commit an impossible crime. Then, they changed the order of their murders, specifically to outwit me. Then they moved Hata Reito's 'Chimera' to Kojin Shrine."
"I see no connection between these acts."
"...I first began to suspect something when I found Chimera at Kojin Shrine. I asked myself why the culprit took the risk of moving the painting, and I came up with an answer."
Ayaka narrowed her eyes in thought, then suddenly reeled back in shock.
"If I remember correctly, Kojin Shrine remained standing even after the landslide, right?"
"That's right. To the culprit, Hata must be someone special. If they brought his painting out to Kojin Shrine... I can only think it was to protect it from the landslide."
The inside of the trailer was silent. It seemed everyone already understood Kamo's meaning. He continued.
"In other words, the culprit knew that there would be a landslide and Kojin Shrine would be the only place to survive. Just like me."
Amamiya ran a hand through his hair and stammered in confusion.
"Is that even possible?"
"At first, I thought I was being absurd. But if you allow the possibility that the culprit is another time traveler, it explains everything."
Genji dropped his gaze to the floor.
"If the culprit is a time traveler, they could have predicted you would keep watch from the cleaning supplies room. It would be the perfect place to keep watch on the Tiger Room, you couldn't pass it up. They could have guessed you'd figure that much."
"So they changed the order of their killings to outsmart me, and staged an impossible crime that was only impossible because I was in the cleaning supplies room... They used their knowledge of the future to make things work out the way they wanted."
After a pause, Kamo looked at the hourglass and continued.
"Another time traveler has changed the past, and you brought me here to undo their changes. Am I wrong?"
For some reason, Hora started laughing.
"You are mostly correct. In actuality, this crime involves not 'another time traveler', but 'another time machine'."
Kamo, who had assumed another time traveler had come back and caused the Deadly Tragedy of Shino, was more confused than ever.
Just what happened in your future?"
"It's a more serious situation than you can imagine... Informing those from the past of the future is strictly forbidden, but just this once, I will break my orders."
Hora had completely lost his light and returned to the appearance of a perfectly ordinary hourglass.
I was born in a research institution called Global Synthesis Laboratory, or GSL. Dr. Bastian was a researcher at GSL, who created two prototype devices for traveling through time and space. One was me, who had an entire world contained within myself and the ability to correct history. The other was Cassiopeia, who only possessed the function of travel through time and space."
"Cassiopeia?"
Kamo couldn't help but exclaim. Hora, in contrast, was calm.
"As a child, Dr. Bastian loved the works of Michael Ende. That was why he named his creation after the tortoise who served as a companion to Meister Hora in Momo... Incidentally, Cassiopeia also possesses the shape of an hourglass and internally houses a quantum computer. In terms of our performance specs and ability to travel through time and space, she is exactly the same as I."
"Is Cassiopeia also bound by the four constraints of time travel?"
"Yes. The only difference between us is that I possess an independent world and time."
"Hmm, so you seem to be an upgrade over Cassiopeia, huh?"
"There is no hierarchy between us. We are mere guides, enabling those who have become time travelers to journey through time and space safely. ...Afterwards, many experiments were conducted by Cassiopeia, and research progressed smoothly."
"I get that much, but why is a time machine causing havoc in the past now?"
"A criminal learned of the experiments being conducted at GSL. Her real name is Alice, but she is more commonly known as Malice."
"She isn't actually a man, is she?"
Kamo had to ask, but Hora didn't take the bait.
"Of course, she is a woman. She was once a brilliant researcher at GSL, and was a global leader in the field of artificial intelligence... Unfortunately, the woman who would become Malice grew jealous of a certain achievement made by a colleague at GSL who had once been her best friend. She went mad and disappeared."
"A former researcher became a criminal? A mad genius sounds like a recipe for trouble."
Both the target and the targeter were worthy of the title 'genius'. Malice, who would do anything to erase the existence of her former best friend, committed many crimes."
"The researcher who was being targeted, did they survive?"
Ayaka asked, her voice trembling with concern. Hora answered surprisingly warmly.
"Of course. Every time, he foiled Malice's plans and thwarted her evil deeds. ...After many failures, she finally gave up on trying to kill her former best friend. Instead, she made a new plot: steal Cassiopeia, return to the past, and prevent his existence to begin with."
Kamo felt a chill at Malice's endless vindictiveness.
"This story is absurd. Did she succeed?"
"In some ways she succeeded, and in some she failed. While she was stealing Cassiopeia, Malice was surrounded by the special forces and was killed. However, she'd prepared for her death. She hacked Cassiopeia and replaced the AI with new data."
"What was the new data?"
"An AI that was a perfect copy of her own mind. The dying Malice herself became a time machine, and Cassiopeia fled into the past... For the sake of convenience, we have dubbed the Cassiopeia whose insides have become Malice 'Dark Cassiopeia', or D. Cassiopeia for short."
"Then, can't you find out where D. Cassiopeia is? Can't you measure whatever sort of sci-fi radiation she gives off or something?"
Hora's voice suddenly grew dark.
"If I could do that, we wouldn't be in this situation. Nobody expected that a time machine would ever be used to commit a crime, so they never developed any way of searching for devices. Even if D. Cassiopeia were right here in the room with us and suddenly threw Kamo and I through time and space... depending on the circumstances, I might not even realize we had time traveled."
"Man, this prototype is terribly designed."
"It hurts hearing you talk like that. I can tell when and where I am if I take the time."
At that point, Ayaka's face changed as though she had suddenly realized something.
"More importantly... could it be that D. Cassiopeia is 'here' now, and is targeting us?"
"Yes. The name of the man Malice was trying to kill is Eugene Ryuuzen. He was a descendant of Ryuuzen Taiga."
Kamo, who hadn't thought that far ahead, was stunned speechless. Hora continued on, calm as ever.
"Dr. Eugene was a genius in the fields of genetic engineering and geophysics. His greatest achievement came in the year 2258, when he foresaw the coming of a major extreme weather event within the next few decades. By his calculations, it would be a catastrophe, completely devastating the global ecosystem and potentially eliminating life on Earth."
"So, did this freak weather actually come?"
Kamo's worried question was answered immediately.
"Just as he predicted, in 2279, an abnormal weather event, the 'Great Calamity', struck the Earth. It was a worse disaster than the one that drove the dinosaurs to extinction. However, thanks to Dr. Eugene's tireless efforts rallying the United Nations to take countermeasures, the damage was kept to a minimum. It wouldn't be an exaggeration to say that Dr. Eugene saved the world."
Kamo couldn't wrap his head around the story, which was too grandiose to believe.
"So to summarize the story so far... Cassiopeia came to the past to wipe out the Ryuuzen family and prevent Eugene from ever being born?"
"Yes. That is her sole purpose."
Amamiya, who was trembling badly enough to be seen even from a distance, spoke up.
"But if Dr. Eugene disappeared, wouldn't that be... bad?"
"I haven't confirmed the state of the altered future, but... Dr. Eugene's research was based on his own unique methods. Given that, the odds of someone else making his discovery of the Great Calamity are less than 1%."
"Are you kidding me? If D. Cassiopeia achieves her goal, there's a 99% chance humanity will perish!"
Kamo's scream made Hora's tone turn doubtful.
"I did warn you that the situation was more serious than you could imagine."
"Do you have to sound so calm all the time?"
"Whatever the case, Malice would do anything to destroy Dr. Eugene. D. Cassiopeia would happily sacrifice all of humanity if it meant erasing his existence... However, I believe it's more likely she plans to use the Great Calamity to create a world where only those convenient to her can survive."
"What the hell... If someone this dangerous is involved, I'd like you to tell me before you drag me along."
Hora ignored him.
"During World War III, enemy attacks erased large amounts of electronic data in many parts of Europe and Southeast Asia. Dr. Eugene's great-grandmother, Ryuuzen Naomi, appears to have lived in one of the affected areas, and as she was a war orphan, all records of her ancestry were lost. Therefore, even within my archive, Dr. Eugene's ancestors can only be traced back to Ryuuzen Naomi."
Hora paused for a moment.
"However, Dr. Eugene had heard stories from his great-grandmother. Stories of how his ancestors were involved in a terrible incident known as the Deadly Tragedy of Shino. Malice had heard these stories and discovered that you, the Ryuuzen family, were Dr. Eugene's ancestors."
Genji frowned.
"But isn't that strange? The Deadly Tragedy of Shino must have been caused by D. Cassiopeia. Why did it occur even before she changed the past?"
"Actually... it appears that even before the past was altered, a series of murders occurred at the villa in Shino, and many victims were claimed by a landslide."
Genji's eyes shot open.
"In other words... whether it was interference from the future or not, there was always a murderer among us, and we were always destined to become the victims of this incident?"
"That is the case."
Kamo couldn't keep quiet. He spoke as though he'd just heard a funny joke.
"If you know all that, then there must be records of the culprit in your archives, right? Even if the course of history has changed now, they'll still help. For the time being, just give me the info already."
"Unfortunately, my archives contain no records of the murderer's identity. After all, the landslide destroyed everything. However, not everything is the same as it is now. Originally, the Deadly Tragedy of Shino was a much simpler incident."
"So it wasn't originally full of impossible crimes?"
"The autopsy reports in my archives state there were no signs of the bodies being mutilated. Originally, the culprit didn't cut up the bodies."
Hearing the words "autopsy report" sent Kamo deep in thought. He eventually asked another question.
"According to your archives, whose bodies were found in the landslide?"
Kamo had previously decided not to talk to Ayaka about this, but now, he decided it had to be done.
"There were five people: Kyuichi, Koki, Soujirou, Tonegawa, and Ayaka. The remaining bodies have all gone missing."
Those were the same five from the future that Kamo knew... the one after history was changed by D. Cassiopeia. Kamo saw Ayaka bury her face in her hands and Tsukie place a comforting hand on her shoulder. He forced himself to ignore her and continued the questioning.
"Are there any other differences? How is your Deadly Tragedy of Shino different from mine?"
"Well, the first incident didn't occur until midnight on August 23rd, two days after it did in yours."
"I see... so that's why you brought me to the 22nd."
"Yes, I acted in accordance with the information in my archive from before the alteration of the past. I had no idea the crime had been committed two days early."
"Even if D. Cassiopeia's influence moved the time table up... this is still strange. Why does D. Cassiopeia keep directing the culprit to commit impossible crimes? An ordinary criminal wouldn't do something like that."
Hora softly answered Genji's skepticism.
"Malice isn't an ordinary criminal. She was even nicknamed 'The Queen of Impossible Crimes'."
Kamo's eyes nearly bugged out of his skull.
"Queen of Impossible Crimes?"
Even Genji and Ayaka, who had stated they liked detective novels, were making indescribable faces. Hora continued in a calm voice that made it impossible to tell if he even realized how surprised they were.
"Malice has devised many impossible crimes in the past. Famous examples include 'The Spaceship Timetable Alibi Trick' and 'The Simultaneous Murder of 1,000 People In Locked Rooms Across The Galaxy'. Daring to intervene in the Deadly Tragedy of Shino could be called a typical move for her, who likes flashy and dramatic events."
Kamo shut his eyes. He felt an awful migraine coming on.
"That's enough of that. I at least understand that the future is ridiculous... D. Cassiopeia is a copy of Malice. So even after coming here to the past, she's still trying to commit impossible crimes?"
"Strictly speaking, D. Cassiopeia cannot commit crimes alone. She cannot act independently like I can, and she can't even time travel unless accompanied by a human."
"So she has a human accomplice."
"I don't know how, but it appears that she's uncovered the identity of the murderer lurking among the Ryuuzen family and is using them as a catspaw. That person must be hiding an hourglass somewhere, just as you are."
"That's a problem. If things get hairy, the murderer can just time travel to escape."
"However, it does give us some information... When Malice was alive, she never trusted another. To minimize the risk of betrayal, she never had more than one accomplice to any crime."
Kamo was a bit surprised.
"Even if that's true, can't D. Cassiopeia have just changed her mind?"
"No. This is one of the major drawbacks of AI made by copying human minds. The AI cannot help but be bound by the human's attachments in life."
"So what you're saying is... D. Cassiopeia can only be working with one person?"
"That's correct, there is definitely only one murderer carrying out her plan by themself."
Ayaka raised her tear-stained face.
"Wait! Won't we be wiped out by the landslide anyway? Why is D. Cassiopeia targeting us like this? We were already destined to die."
"She's probably made a deal with the murderer."
Hora's words made Kamo start trembling.
"The murderer within the Ryuuzen family's goal is to kill those gathered at the Shino villa. No, their real purpose might be to wipe out the Ryuuzen family entirely... On the other hand, D. Cassiopeia's goal is to find a time traveler who will enact their will, and have them kill everyone who could potentially be an ancestor of Eugene, in other words, the descendants of Ryuuzen Taiga."
"Indeed, their goals are generally in alignment."
Even though it was a summer night, Kamo couldn't stop shivering.
"I think I'm starting to get it. D. Cassiopeia and her time traveling murderer... they're the true identity of the curse of the Ryuuzen clan, aren't they?"
"Thank you for your understanding. D. Cassiopeia probably demanded absolute obedience from the culprit in exchange for lending her wisdom to their cause. Since the murderer had a deep grudge against the Ryuuzen family, I believe they gladly accepted her proposal."
Kamo opened his mouth, even though his teeth wouldn't stop chattering.
"After committing the Deadly Tragedy of Shino, did D. Cassiopeia and the murderer travel through time and murder all of Fumino's descendants, making them all look like accidents?"
"Yes. That is the truth of the phenomenon that was called a curse."
"...Why!? Why is this happening to us? What did we do!?"
At the sound of Ayaka's heartbreaking cry, both Genji and Tsukie lowered their heads. Hora continued as though he hadn't noticed.
"Whatever the case, as a result of Kamo's appearance, D. Cassiopeia is now acting in a different way than she had in the already altered past. Due to the changes to the already altered past, the world is growing unstable, and phenomenon unknown even to me have already begun."
Genji frowned and looked down at the hourglass.
"What exactly is happening?"
"For about an hour now, there has been a dramatic abnormality in my space-time positioning system. Specifically, there is a large discrepancy between our current position in time and space and the location and time measurements derived from local gravitational wave analysis."
"I don't really understand the details, but how could that have happened?"
"I believe the main reason is a distortion in the unstable world, but even I don't know the details... I will need to recalculate to correct this discrepancy, which will take 12 hours. You will not be able to travel through time and space until the correction is complete."
As he half-listened to Hora's explanation, Kamo thought of Rena, the woman he'd left in 2018.
She was the last survivor of the Ryuuzen clan. She was sick, and her life would soon end. Kamo didn't care if she was Eugene Ryuuzen's ancestor, or it was one of her cousins. As long as he could have her, that would be enough for him.
However, there was a question he couldn't get out of his head.
"...Why?"
"It works similarly to a GPS. While traveling through time and space, it is impossible to travel safely if there is even the slightest discrepancy between the value entered and the actual starting point, so it is necessary to align with gravitational wave measurements-"
"That's not what I was asking. Why did you chose me as your time traveler?"
Hora gave a deep sigh that didn't sound right coming from an AI.
"My existence was top secret even within GSL. Even Cassiopeia was unaware of my existence, and Malice believed her to be the one and only time machine in existence. When Dr. Eugene discovered that Cassiopeia had been taken... he knew from the data left in GSL that she was targeting the Deadly Tragedy of Shino. In response, Dr. Bastian and I traveled to 1960. Our goal was to stop D. Cassiopeia and prevent the alteration of history."
"But you didn't come here with Dr. Bastian. You came here with Mr. Kamo. What happened?"
The hourglass's response to Ayaka was bitter.
"Dr. Bastian and I lost control and arrived 10,000 years in the past... Was it due to instability from D. Cassiopeia's interference in the past, or had Malice left malicious data in GSL's computers as a trap? I still don't know."
Everyone couldn't help but let out a groan at that ridiculous story. Hora's tone became sad.
"Due to the constraints of space-time travel, it took twelve hours before we could move again. In parallel with recharging my energy, I also had to determine our coordinates using the All Time and Space Positioning System... In the end, Dr. Bastian couldn't survive that long. He was attacked by what appeared to be a saber-toothed tiger."
No one spoke for a time. After about twenty seconds of silence, Kamo asked:
"Then what happened to you?"
"There was nothing I could do without an accompanying time traveler. I was buried deep underground. Dr. Bastian had given me the strength to survive a thousand years of use, so my vessel could withstand 10,000 years. However, it seems my insides were different."
Thinking in human terms, 10,000 years was an unimaginably long time. If the AI was based on human thoughts, it might have felt terribly long for Hora as well.
"Those long years changed me. I learned the true meaning of despair, which AI aren't supposed to know. I feared...that my prison would last until the end of time. But I was lucky. At the end of 2015, I was dug out by an archaeologist. I was finally free."
Kamo recalled that the urban legend of the Hourglass of Miracles emerged around 2016.
"Then you started moving from person to person, right?"
"And as a result, I have come to be known as 'The Hourglass of Miracles', but that is a misinterpretation of my abilities. I don't have the power to bring about miracles."
"Wait, I heard once that someone used the power of the hourglass to win big on long-shot odds on a horse race. I don't think it's true, but..."
"My archive includes all information on past horse races. I used it to compensate him for his cooperation."
"Hey, what happened to not rewriting the past?"
"I learned much in my underground prison. For the sake of averting the extinction of humanity, we cannot choose our means. And I found the perfect person to stop D. Cassiopeia and her murderer from committing their crimes... You, Kamo."
Even now, the chill running down Kamo's spine hadn't let up. Eventually, he asked in a low voice.
"Why are you so sure I'm the right person?"
"You're Ryuuzen Rena's husband, and you possess intellectual abilities above a certain level."
"Is that it?"
"You also had a strong drive to help your wife by any means necessary... If all of these qualities are put together, there is no one more qualified than you."
Kamo shook his head in resignation.
"I don't think anything you've said is a lie. But I get the feeling you aren't telling me the whole truth, either. I think there's another reason you chose me."
For some reason, the hourglass's voice sounded like it was challenging him.
"Do you have the nerve to say the real reason?"
I do."
"O-ho."
"Even if D. Cassiopeia didn't know about you, she figured it out as soon as she saw me. I'm another time traveler with another time machine, and I'm here to stop the Deadly Tragedy of Shino. That much should have been obvious as soon as I first appeared."
"I suppose so. The number of unexpected guests suddenly increased, and you didn't even hide me... that is, the hourglass."
Kamo placed a hand over his heart and continued.
"To be blunt, I'm the biggest nuisance for them. It wouldn't have been surprising if they'd killed me before Kyuichi and Koki."
Even though he felt his fingertips tremble against his chest, he couldn't stop them.
"And yet, they didn't lay a finger on me. They could have easily poisoned me or killed me any way they pleased... they could have killed me and then stolen you, Hora."
"It's just because you don't have Ryuuzen family blood, Mr. Kamo."
He heard Ayaka, but he already knew that wasn't it.
"D. Cassiopeia is a cold-blooded simulacra of a human; she'd never show mercy to someone who got in her way. The only reason I'm still alive is because there's a practical reason they couldn't kill me."
"And what reason would that be?"
Hora's voice was as provocative as ever, but it wasn't the least bit disturbed. Kamo, on the other hand, was helplessly shaking.
"D. Cassiopeia was afraid that killing me would cause a time paradox."
Tsukie, who had been silent this whole time, blinked in confusion.
"What do you mean?"
Kamo looked back at her with a dissonant smile.
"To put it plainly, I'm Malice's ancestor... If D. Cassiopeia is a mental copy of my descendant, then killing me is the same as a descendant killing their own ancestor and creating a time paradox. Am I right, Hora?"
Even as he asked, he couldn't believe the smile on his face. He felt sick.
"That is correct. Malice's real name is Alice Kamo. She is your descendant."
Kamo burst into uncontrollable peals of laughter.
"What is this? I don't even have any kids yet, but my descendant is already a murderer!"
"I don't know if this will bring you any comfort, but the shared genes between Malice and Kamo are only a small portion. That said, there are certain similarities in your personalities."
Kamo stopped laughing.
"But... at least I'm not a criminal."
"Right now, yes."
Hora said that coldly. Kamo shut his eyes in fear.
The only reason he'd have said that is because his archival records showed that he'd become a criminal in the future. In the end, it was destined that Kamo would marry a woman other than Rena, and their child would become the ancestor of Malice.
"Because you knew all that, you thought you couldn't trust me, so you kept everything quiet and dragged me here by force, right?"
Hora didn't answer no matter how much he asked.
Eventually, he noticed his hands had stopped shaking. He could only view the situation as having gotten worse, but for some reason, he'd completely calmed down. Perhaps he was like Malice after all. They were both insane.
"Now I get why you chose me. First, because you knew that if you turned someone else into a time traveler, they'd get killed, so you chose me, who they can't kill. That, I get. Second, you knew that whether I succeeded or failed, you'd still have a chance to save history."
Genji looked at Kamo with a surprising amount of sympathy.
"It's tragic... If you uncover the truth and incapacitate the murderer, you can save the lives of those who were to be killed afterwards. But even if you fail in your deduction... if you die here, the future Malice won't be born."
"No matter how things go, there's still a chance to prevent Eugene from being erased... If I can't figure out the truth of the incident, you'll time travel into outer space or to the bottom of the ocean and kill me, do I have that right?"
"Yes, I was considering moving you to the ocean floor as a last resort. As long as I can accomplish my purpose, I don't care if I am incapacitated again."
The ground fell out from under him, and there was nothing Kamo could do but laugh. It wasn't another sudden burst of laughter, but a relaxed, natural laugh.
"I get it, you have a determination of your own... So, what now? Should I keep on playing detective? Or should I just die for Rena?"
Whatever he sensed in that voice, Hora returned to his original calm voice.
"There are two reasons why I hid the existence of D. Cassiopeia. One is because I feared that if you knew the whole story, you might abandon me and join her."
"I wouldn't do that."
Hearing that, Hora lowered his voice.
"I don't understand. Your desire to protect those of the Ryuuzen clan is genuine. Your personality is so different from the data recorded in the archives. I don't believe D. Cassiopeia has tampered with this part of history, so how could there be such a discrepancy?"
"...Because I met Rena."
Kamo spoke in a voice no one else could hear. He had changed so much since meeting her. That was something he'd been forced to admit long ago.
At that moment, the terrible chill that had disappeared returned once again. Kamo couldn't take it anymore. He closed his eyes. He knew he wasn't sick or afraid, but trapped in a deep despair.
"Did you say something?"
Kamo realized he had covered his face with both hands without realizing. His throat was hot and he felt like he was about to cry, but he choked back his tears.
He gave himself a moment to calm down, then shook his head.
"It's nothing... more importantly, you said there was another reason why you didn't tell me about Malice. What was it?"
"I was afraid that if you knew the future, it would drastically change, threatening the existences of both Dr. Eugene and Malice."
Kamo didn't quite understand.
"Wasn't that what you wanted, for Malice to never be born?"
"Not at all. Before she turned to crime, Dr. Alice was one of a kind."
"She might have done some good, but I don't think it makes up for all her crimes."
"Unfortunately, the effects humans have on their world are complex."
"What do you mean?"
"When Dr. Alice and Dr. Eugene were still friends, they stimulated each other and frequently collaborated on advanced research projects. ...If he had never met her, Dr. Eugene wouldn't have become a researcher, and vice versa. Alice's AI research was done by referring to Dr. Eugene's work in evolutionary biology, and Dr. Eugene used an AI of her creation to analyze the abnormal weather patterns."
Ayaka's cheeks turned a bit red with excitement as she said something to herself.
"The relationship between them was like two sides of the same coin, and neither one could be removed without the other..."
"That is why I didn't tell Kamo about Malice. I was afraid that if you came to despise Malice, you would take action to prevent her birth... Kamo, taking your life is my last resort, but it could never be an act for the sake of the future."
Large, heavy raindrops hit the roof of the trailer, and the wind rocked them side to side. It took a full minute before Kamo spoke again.
"In the end, our only choice is to solve the mystery of the Deadly Tragedy of Shino, catch the murderer, and retrieve D. Cassiopeia from wherever they hid her, right?"
"Yes. That is our best option."
Tsukie, who had listened quietly to the whole story, crossed her legs on the bed.
"...Genji, Mr. Amamiya, do you believe what you've just heard?"
Genji took out a cigarette and twirled it between his fingers for a time, but then he looked up.
"I think we can believe it. The story he and Hora told was interesting, so it must be true."
"Of course you'd say that. What about you, Mr. Amamiya?"
Amamiya stared at Tsukie, rubbing a wet towel with his hands as he spoke.
"A lot of the story went over my head, but I trust Mr. Genji's judgement."
When she heard that, she smiled. It was the first time Kamo had heard Tsukie laugh.
"In that case, I'll try to believe you, too... Whatever the case, it's troublesome that the murderer has a time machine. There's no way to prove that they didn't use D. Cassiopeia's abilities to move the bodies and themself."
Kamo smiled bitterly.
"However, it isn't fair to claim it's an impossible crime while using space-time travel. An impossible crime is impossible because supernatural phenomenon don't exist."
"Not necessarily... In the past, there were many cases when Malice performed impossible crimes without resorting to special abilities that no one else knew about. However, it was different if the ability was understood."
Kamo opened his eyes.
"In this case, Hora's here, so Ayaka and I already knew about time travel from the beginning... From D. Cassiopeia's perspective, time travel could be considered a known quantity. Is that what you're saying?"
"It is. From her point of view, incorporating time travel and spacial warps into the crime shouldn't be considered unfair."
Hearing those words, Genji put his hand on his chin, which had begun to grow stubble, in thought.
"But.. due to the second constraint of time travel, when you move, you must move at least the size of a cube with 3 meter sides, right? The ceiling of the villa isn't that high, a bit over 2 meters. So if you try to move within the building, no matter where you set the cube, it will always take a part of either the ceiling or the floor. Where are the marks from the areas gouged out? The fact that there were none proves that nobody used time travel to leave the villa."
Ayaka looked up in surprise and asked Hora something.
"By the way, can you carry body parts?"
"It is possible to transport a human body alongside a time traveler, but it isn't possible to move anything without a time traveler."
"I see, so it isn't possible to move only the body parts..."
"Yes... But any living person can be forcibly moved as a time traveler."
In fact, Kamo had been forced to time travel here without his consent. That must have been because he'd been forcibly designated a time traveler.
After getting her answer, Ayaka muttered in thought.
"Could it be possible to time travel even if you were separated from your time traveler?"
"Yes, there is no need to keep the time machine close to you. Both Cassiopeia and myself can travel through time and space as long as there is a time traveler within a meter or so of us."
Kamo leaned forward, surprised.
"Oi, is that really possible?"
"Of course, there is no problem even if there are obstacles between me and the time traveler... Why? Is there something that bothers you?"
Kamo's face went pale, and he spoke without thinking.
"If you can do something like that, then... at that time... was the murderer...?"
However, Genji cut him off.
"I don't know about that. Considering the conditions we just heard, I don't think time travel could have been used in any of the crimes so far."
"It is as Genji says. Due to the third constraint, it is not possible to move to a desired location with pinpoint accuracy. An error of ± 5 meters would be quite large inside a villa."
Kamo blushed as he realized his mistake.
"Isn't this a stupid story? ...Even if you tried to appear in a large room, there'd be tons of furniture and stuff in the way, so it'd be too dangerous."
Genji took the opportunity to summarize the case.
"If you think about it, there's no way that time travel was used when the criminal carried my brother's head and Koki's torso outside. At the time, the ceiling and floor precluded anyone from using time travel from inside the building. There were no three meter empty spaces to return from the outside, and it was impossible to only move the bodies."
Tsukie also nodded at that.
"It's the same in Grandfather's case. There were no spaces that meet our conditions... so it would be impossible to force Grandfather out of his room as a time traveler without leaving any traces on the ceiling or floor."
Amamiya gave a modest nod of his own.
"And as for Ms. Tonegawa, there's no need for time travel in the first place. Anyone could have poisoned her."
Hora delivered the finishing blow.
"You are all correct. Even if we assume the existence of technology for space-time travel, this is still an impossible crime."
*
The first thing Kamo did was subject everyone else to body searches.
He did so to check if anyone was hiding D. Cassiopeia, but of course they didn't find any hourglasses in anyone's clothes or belongings. At Kamo's suggestion, it was decided that they would continue to subject everyone to random, unannounced searches.
Amamiya, who was in the kitchen, seemed to get tired of standing and sat down in the bedroom. Probably because he was too shy to approach Tsukie and Ayaka, he sat down at the bedside table, far from anyone else.
Just then, Genji sat down on the trash can in the kitchen and made a sudden noise, as though he'd forgotten something.
"Ah, I got so absorbed in all that talk of time travel I completely forgot... I actually wanted to talk about something completely different."
Ayaka looked at Genji with confusion. He answered with a sad expression.
"I don't think Ayaka or Tsukie have ever heard this story before. I only found it out myself after considerable searching. Mr. Kamo, I have to tell you about the secret behind Hata Reito's birth."
"Ah, I thought something like this would come up. Was he the illegitimate child of a Ryuuzen?"
Kamo was so brutally straightforward that Genji couldn't help but laugh.
"Officially, Reito was my maternal cousin. But in actuality... he was both my brother and my uncle."
Kamo was confused.
If he were the illegitimate son of Taiga or Genji's father Eitaro, that would make Reito an uncle or a brother. But it seemed impossible for one man to be both. As he struggled to recall the Ryuuzen family tree he'd studied from the archives long ago, he realized a possibility.
"Could it be that he was simultaneously a brother from one side of the family, and an uncle from the other?"
Genji nodded solemnly.
"My mother, Ryoko, was a servant at the main house when she was young. Of course, that was before she met my father, Eitaro. And... Grandfather impregnated her."
Small gasps came from both Ayaka and Amamiya. Tsukie stared at the floor in silence. Genji continued to speak in a sad, far away voice.
"Grandfather was afraid Grandmother would find out about his impropriety, so he immediately had my mother sent back to her parents' home. She gave birth there, and the baby was raised as the son of my mother's brother, my Uncle Hiromitsu."
Kamo winced.
"So, Hata Reito... to you, he was both a half-brother and a paternal uncle?"
"Yes. My mother's family, the Hata, were poor, and I think Uncle Hiromitsu needed the money Grandfather had promised to pay for child support. That's why he had no choice but to accept that his sister had grown pregnant out of wedlock. I suppose he had no choice but to cry himself to sleep every night."
"Grandfather... why?"
They couldn't imagine how upset Ayaka was to learn about a side of her grandfather she'd never suspected. Eventually, Genji continued, his face growing even darker.
"Later, my mother was given a job at Grandfather's company. Probably the reason she was paid so much more than a woman her age could have ever asked was because Grandfather was trying to atone for his sins... That was where she met my father, Eitaro."
Kamo was confused again.
"So why did they get married?"
"Grandfather kept Reito's existence a secret, and my father had been gone studying abroad for a long time, so he didn't know a thing. He fell in love with my mother at first sight."
"But-"
"It's unthinkable, isn't it? For a father's mistress to become the son's wife? At first, I think my mother hated my father and tried to push him away. But in her own way, she was unhappy. And... my father was an honest, kind-hearted man who wasn't suited to business. And above all, his feelings for my mother were real. It may have taken a while, but my mother cherished my father. I think she even came to love him."
No one could say anything. Genji continued his painful confession.
"Even though he knew everything, Grandfather didn't object to the marriage. He hated the old ways and old customs with a passion that sometimes became madness... In fact, Grandfather offered to financially support the Hatas and promised to take in Reito and raise him as a Ryuuzen, and even give him a share of the inheritance equal to mine and my brother's. For the sake of her family and her son, I don't think my mother had any choice."
The expressions on Ayaka and Amamiya's faces weren't a bit sympathetic. Genji, seeing this, finally turned his head down.
"Eventually, my mother and father were married, and a distorted situation arose in which they took in Reito and raised him as their own... I pray that her life was happy right until she was killed in the air raids."
For some reason, hearing his story made Kamo think of Rena.
Kamo also wouldn't have cared what sort of secret she held, even if it was something wider society would never accept. He wondered what Ryoko had thought about her marriage to Eitaro.
He took a deep breath.
"Whatever the circumstances that led there, Ryoko was able to live a stable life with her three children... That's an irreplaceable gift. That's why I believe she was happy."
Genji seemed surprised, but he soon smiled.
"Thank you."
"By the way, did Reito ever learn the circumstances of his birth?"
Genji narrowed his eyes as if trying to remember something.
"I don't think so. At least, he didn't know when I was a child."
"But even if Taiga kept it a secret, some of the relatives must have found out."
"Yes, more than a few people figured it out. Koki's mother, Aunt Shoko, for example. I learned about the story from her when she was drunk. And there were others..."
"Father knew. So did Tsukihiko."
Tsukie interjected without changing tone in the slightest. Genji's eyes went wide.
"I know Soujirou knew, but when did you learn? This all happened before you were born."
"I learned about it when Tsukihiko and I secretly read my Father's hidden diary."
Genji, who seemed to find that surprising, smiled bitterly.
"Is that so... Come to think of it, my aunt and uncle's attitude towards Reito was always cold. I guess that was because they knew the secret."
Reito's share of the inheritance was supposed to have been quite large. It wouldn't have been surprising if some of his relatives found that dissatisfying.
Kamo thought for a moment and asked the first question that came to mind.
"Why did Soujirou and Shoko keep quiet about all this? They could have revealed everything to Eitaro and questioned Taiga's decision."
Genji lowered his eyes as though he were struggling to answer, so Tsukie spoke for him.
"Father was extremely jealous of Mr. Eitaro, the heir to the Ryuuzen clan. I read in his diary... when he saw Mr. Eitaro raising his wife's illegitimate child without realizing, Father felt a twisted joy. On the contrary, he may have been planning to use the secret as material to extort Eitaro and Grandfather in the future. Father is that kind of man."
Her direct, heartless declaration convinced everyone she was telling the truth. Genji gave a deep sigh.
"Let's get back on topic. Reito went off to war and returned in 1946, but he'd become a different person. He tried to distance himself from both myself and Kyuichi. I thought it was from what he'd gone through during the war, but it seems I was wrong."
"You mean someone told Reito the secret of his birth?"
He gave a small nod.
"It's possible my mother told him everything before he left for the war."
When the red paper came, Ryoko must have known there was a possibility that she'd never see her child again. It seemed only natural she'd choose to reveal her secret while she still had a chance.
"And then, two years later, Eitaro died and Reito went missing?"
"...Even now, I can't forget the telegram I received in Hong Kong."
Genji paused for a moment before speaking again.
"I couldn't accept my father's death. He'd been in such good spirits when he saw me off at the port. It also seemed impossible that Reito would just leave us. That's why, when I returned home, I immediately questioned Kyuichi."
Ayaka went pale at the mention of her father's name.
"And... what did Father say?"
"He tried to pretend he didn't know anything. But Kyuichi was a terrible liar, so I knew right away that he was hiding something."
Genji turned back to Kamo.
"After that, I spoke to Grandfather, Soujirou, and Tonegawa, but it seemed they were all hiding something and I couldn't get a straight answer. I couldn't accept that, so I tried questioning Aunt Shoko while she was drunk, but... it was no use."
Tsukie hugged her shoulders.
"Father was the same way. When I tried to talk to him about that day, he just scolded me and wouldn't tell me anything."
At that point, Kamo could see two possibilities.
One was that Hata Reito had poisoned Eitaro and fled. The other was that someone else had come to the same conclusion, killed Reito, and dumped his body somewhere.
The second one felt closer to the truth... The murderer patterning their crimes on the Nue made it look like it was intended as revenge for Hata Reito.
Once again, Kamo looked around at all the faces in the trailer.
In 1948, Genji had been overseas, and Tsukie and Ayaka were ages eight and one, respectively. Amamiya hadn't even been taken in by the Ryuuzen yet. There was nothing more he could get out of any of them.
Kamo gave a small nod, then spoke quietly.
"I'm sure the only people who really know what happened back then are Soujirou and the murderer. Tomorrow, I'll ask Soujirou directly."
"Assuming he lives that long," Hora's voice rang out.
Kamo glared at the hourglass. Even though Hora was supposed to be an ultra-high-spec AI from the future, he sure couldn't read a room.
Kamo picked up the hourglass and tossed it into his breast pocket, leaving the chain around his neck. He hoped doing so would be enough to block Hora's camera.
"It's useless. I was designed such that, even if I no light reaches me, I can accurately see my surroundings to a range of about one meter... This is an essential function for safe movement through space and time."
Kamo growled "Isn't there any way to shut you up?"
Hora didn't seem to understand why he was so angry, and his answer was confused.
"If you soak me in water, I think my voice would have a harder time reaching the air. If you wish to silence me forever, my weak point is fire... but you aren't being serious, are you?"
Kamo didn't answer that. Even Hora knew to shut up now.
Perhaps simply unable to take the awkward silence, Genji suggested they review the incidents so far.
They still had time until dawn, so the five of them decided to think about how D. Cassiopeia and her accomplice had committed the series of impossible murders. ...Thus far, there were four major problems standing between them and the solution.
① How had the murderer gotten the head and torso out of the building without being seen?
② How had Taiga gotten out of the Dragon Room while the second floor hallway was being monitored?
③ Who was the body in the pizza oven? Was it really Taiga?
④ Whoever the corpse was, where had their legs gone?
Although everyone gave their theories, the discussion never went anywhere. That was because nobody could come up with a hypothesis that fit the evidence.
As this was going on, everyone began to feel varying degrees of exhaustion. Kamo briefly suspected that they'd been given sleeping pills with dinner, but he quickly realized that wasn't necessarily the case.
Kamo and Ayaka had been up all night in the cleaning supplies room on the 22nd. Amamiya and Genji had also been up all night in the recreation room on the 21st, and it was hard to imagine they'd been able to sleep well the following night after the murders. Tsukie, the only one who hadn't pulled any all-nighters in the past two days, had boasted that she usually slept 11 hours a day, so she probably wasn't cut out for going long without sleep to begin with.
Ayaka, the youngest, was the first to fall asleep.
Amamiya noticed that she was breathing heavily, and retrieved a bath towel from the cupboard and gently draped it over her. Kamo also woke with a start near the trailer door and opened the lid of the pocket watch on the table. The dial showed 2:03.
Genji looked at it and murmured something.
"It's already 2:00?"
Kamo felt the same way. Judging by his internal clock, it didn't even feel like 1:00 yet. Tsukie yawned, then smiled at the others.
"It's been a long time since I last stayed up this late."
Amamiya remembered that he'd left his watch to dry, so he went to the kitchen to retrieve it. When he saw it, he rubbed his chin in confusion. Even though he was still young, his skin was as fine as a woman's, and he barely had any stubble.
"My watch says 2:12... It's supposed to be waterproof, but I guess with rain this heavy, there are limits to what can be done."
Glancing over at the watch, Tsukie gave her opinion.
"It doesn't matter which of them is right. I don't want to be bound by time, so I don't carry a watch at all."
With that short declaration, Tsukie shut her eyes. Genji also reached for his watch, which was still wrapped in a towel.
"Looks like Ayaka's watch was correct."
Kamo looked at his watch and saw that the hands pointed to 2:02.
After reapplying his watch to his left wrist, Genji reached for Ayaka's pocket watch. Kamo noticed him going to wind it, and suddenly stood up.
The back of his neck hit the lantern. Their only source of light went shaking, causing the shadows to wriggle long and short within the trailer.
He rubbed the back of his neck, fearing he'd burned himself, but he didn't feel any heat where the lantern had touched him. It looked like he'd gotten lucky.
Next to him, Genji froze in place and stared at him.
"What is it?"
"Nothing, I just... I thought Ayaka had a habit of winding her watch all the time, but I guess I was wrong."
Kamo blushed a bit with embarrassment, but Genji answered with a nostalgic look.
"Yes, she knew it was necessary, so she did it. The watches Grandfather got us are all hand-wound, and they were deliberately designed to need lots of attention... I think Grandfather considered them a metaphor for family."
Kamo reached out and took the pocket watch, which had been left unwound.
"So you mean that you need to be careful to regularly maintain it?"
"That's right. Grandfather was also careful to make sure his watch never stopped."
Amamiya also nodded at his words. Kamo thought for a while.
"Come to think of it, I think Ayaka told me the mainspring of this watch only lasts half a day..."
"Yes, it lasts exactly 12 hours. That's how it's designed."
Hearing Genji's words, it seemed Hora couldn't keep quiet any longer, and he began to glow in Kamo's pocket.
"Even for 1960, that is a rather inconvenient specification."
"I'm not gonna take that from an hourglass. You can only measure five minutes at a time!" Kamo replied.
His pocket began to glow red. Apparently, that meant Hora was angry.
Then Tsukie, who everyone had thought was asleep, opened her eyes.
"Father has a watch just like the one in Grandfather's room. But Grandfather and Ayaka are the only ones who actually wound the watches multiple times a day. That's the gap between ideal and reality."
Kamo couldn't help but smile painfully as he returned to sit by the door. Her analysis was harsh but true.
He decided to borrow Ayaka's pocket watch.
He felt bad, borrowing a memento of someone's mother, but he would ask permission to keep it a few more hours when she woke up.