3
There was a faint sound of water.
...A stream? Yuma opened his eyes slightly and sat up. As soon as he did, a severe pain ran through his back to his waist, making him groan.
Ah, right. He had fallen asleep after being pushed down the stairs.
Fully awakened by the pain, Yuma looked around. The room was dimly lit by indirect lighting, and the blackout curtains were closed. Tsukiyo had probably been thoughtful enough to do that so he would have an easier time sleeping.
“How long was I out...?”
His mouth was dry and his voice cracked. Yuma reached out and pulled open the curtains beside the bed. Outside the massive glass window, pitch black spread out before him.
“...What?”
His brain froze. Yuma quickly turned to his watch. The hands showed just after nine o'clock.
Nine? It was dark outside, so was that 9:00 P.M.!?
Yuma leapt out of bed, too distracted to worry about the pain.
Had he been asleep for almost half a day? Had he wasted that much of the precious time he had until the police arrived? Slick sweat began pouring from every pore in his body.
“Ms. Aoi!”
Yuma looked around for the great detective, wanting to complain that she hadn't woken him up. But she was nowhere to be seen. His heart began hammering in his chest.
Could Tsukiyo have left him to investigate the Tower on her own? And then been attacked by the culprit...?
Yuma put on his shoes and made for the door to search for Tsukiyo. After he unlocked it and just as he put his hand on the knob, he noticed the sound of water.
Come to think of it, he had woken up to that sound. Where was it coming from?
Yuma strained his ears, and traced the sound to the bathroom. He put his ear to the door, and could definitely hear the sound coming from inside. Someone in the shower?
Yuma took a deep breath and called out “Ms. Aoi!” The sound of the shower instantly stopped.
“Ah, Yuma. Are you awake?”
Hearing Tsukiyo's voice from beyond the door, Yuma felt such relief that his legs almost gave out.
“What are you doing in my bathroom!?”
“What? I'm taking a shower. I forgot to bathe last night, and I've been so engrossed in solving the mystery that my body got all sticky. Plus, I used my brain a bit too much while you were asleep and tired myself out, so I thought a nice hot shower would help to refresh me. Ah, no peeking! I don't want our precious friendship ruined over something like that.”
“I wouldn't do something like that!”
Yuma found her nonchalant response rather irritating.
“Of course not, Yuma is a gentleman. I'm lucky to have such a partner. I'll be right out, so wait just a moment.”
The sound of the shower started back up. Yuma gave a deep sigh and stepped away from the door.
After a few minutes spent sitting on the couch, the bathroom door opened and Tsukiyo emerged, wearing a shirt and pants, drying her short hair with a bath towel. Yuma was a bit shaken by the sensual aura of the great detective emerging from the bath.
“Sorry to have kept you waiting. I feel so refreshed...”
Tsukiyo approached the dresser. A folded suit jacket and an ultramarine tie had been laid out.
“You got a change of clothes?”
“Of course. You can't feel refreshed wearing dirty clothes. I changed in the Fifth room.”
“But they're the same clothes.”
“This is my uniform. Ever since I was a student, I've wanted to be a great detective, so I dressed like this. I was very popular with my female underclassmen. I got love letters every day. Jealous, Yuma?”
“So you went back to your room to get a change of clothes, then came back to take a shower here? You could have just showered in the Fifth room.”
Tsukiyo frowned.
“Even if I look like this, I'm still a woman. It takes me longer to bathe than a man. I need a lot of care.”
She said that, but as far as Yuma knew, it was unusual for even a short-haired woman to not use a hair dryer. Yuma twisted his lips.
“In that case, why didn't you take a nice long bath in your own room?”
“What if you'd been killed in the meantime?”
As Yuma sat speechless, Tsukiyo continued.
“If I was just going to the Fifth room to change, I could have been back in two or three minutes. I can't imagine you being killed that quickly. But my baths take about thirty minutes. Do you think I could leave you alone for that long in your state?”
“You could have just locked the door...”
“Ms. Tomoe's body was found in a locked room. Locking the door doesn't mean you're safe. Have you forgotten? Someone pushed you down the stairs.”
“There's no way I could forget that.”
“Then you understand that showering here was the reasonable choice?”
“Yeah, I understand. But...”
Yuma's eyes sharpened.
“Why didn't you wake me? It's already nighttime.”
“What? You didn't tell me you wanted me to wake you at a certain time.”
“That should have been common sense. You should have woken me after two or three hours.”
“Don't you think it's unreasonable to expect common sense from a great detective? Besides, you looked so comfortable snoring away, I couldn't stand to interrupt you. You have a cute sleeping face, Yuma.”
Yuma held his head in his hands at her rude answer.
“Wasting almost half a day when we're in such a desperate situation...”
“Wasting?”
Tsukiyo sounded shocked.
“What are you talking about? This was an excellent use of time.”
“...What do you mean?”
When Yuma raised his head, the corners of Tsukiyo's mouth raised in a grin.
“I told you while you were asleep I would draw conclusions from the information we've obtained thus far. While you were wandering in dreamland, my little grey cells were working away, dismantling the mystery of The Glass House Murders.”
“You mean you know who the culprit is!?”
When Yuma shot off the couch, Tsukiyo gave him a taunting smile.
“I wonder.”
“Don't dodge the question, now is no time for jokes.”
“I'm wounded. That wasn't a joke. If there is a hypothesis I'm confident in, it's already stored in the labyrinth that is my mind.”
“What's the hypothesis!? Who on Earth committed the locked room murders, and how?”
“Calm down. A hypothesis is just a tentative theory. I can't give you a half-baked explanation, even if you are my partner. I won't say anything until I have clear evidence.”
“And where can we find clear evidence?”
“At the scene, of course.”
Tsukiyo picked up the tie lying atop the dresser, tied it around her neck with practiced hands, and threw on her jacket.
“Yuma, how's your injury? Can you move?”
“Huh? Well, I'm a bit sore, but the rest seems to have done me good. I can move normally.”
“You rested up and healed, and I continued the investigation. In other words, this half a day was extremely productive. Now, Watson, onwards! To the final investigation!”
Tsukiyo, having returned to her men's suit, proudly declared.
“Where are we going?”
“You'll know if you follow me. Oh, by the way, Yuma, do you have a stethoscope?”
“A stethoscope? Of course I have one, but why?”
“Bring it with you. We'll need it later.”
“We'll need a stethoscope?”
Yuma asked, frowning, but Tsukiyo urged him “Just hurry,” so he had no choice but to take his favorite stethoscope from his doctor's bag.
“Now we're ready.”
Without explaining a thing, Tsukiyo made for the entrance. Yuma hurriedly called out
“Wait.”
“What? I was just getting excited.”
“I need to use the bathroom first.”
“The bathroom? You want to go to the bathroom right after I've taken a shower there? Do you have a fetish?”
“No! Don't say that! I just need to use the toilet.”
“I'm kidding. Don't get so upset! Come on, hurry up and get it over with.”
Tsukiyo waved her hand. Yuma frowned, went to the bathroom, and locked the door from the inside.
Standing in front of the Western-style toilet, Yuma urinated. He zipped up his pants, then carefully, noiselessly, lifted the lid of the tank. The brown pill case was still floating in the water inside. Yuma grabbed it, flushed the toilet, and shoved it in his jacket pocket.
Tsukiyo had completely returned to the role of great detective. There was no way of telling when she would identify the real culprit. In that case, it was better to keep the pill case on his person so he could use it quickly.
“Yuma? Are you done yet? You struggling in there?”
“I'll be right out!”
Yuma exhaled all the air that had built up in his lungs and left the bathroom.
They left the fourth room, locked the door behind them, and went down the stairs. When Tsukiyo reached the first floor, she went straight into the game room. When she opened the door, Kuruma and Sakyo, sitting on the sofa, turned to them warily.
“Oh, it's you two.”
Kuruma sighed in relief.
“Dr. Ichijou, are you alright? You had a nasty fall last night.”
“I'm sorry to have worried you. I'm still hurting, but it doesn't look like I was seriously injured.”
“That's good to hear.”
Tsukiyo approached Kuruma, who nodded at her, then turned to Sakaizumi lying on the sofa. There were several wine bottles lying around him.
“How is Mr. Sakaizumi holding up?”
Tsukiyo approached Sakaizumi and gave him a light shake. Sakaizumi groaned and brushed off his hand.
“It's as you can see,” Sakyo said, looking down at him. “Ms. Tomoe's death must have come as an enormous shock to him. He cried for a while, then gulped down bottle after bottle of wine, and now he's like this.”
“And what about you two? If you'd like a change of scenery, you're free to accompany us for a while.”
As if trying to dispel the oppressive atmosphere, Kuruma spread his arms in an unusually cheerful manner.
“That's right, since there's a poker table here, why not talk about mysteries involving cards? The first things to come to mind are The Villa Lilac Case by Ayukawa Tetsuya and Find the King by Norizuki Rintaro. There's also 11 Cards, The Card Murder Case-”
“A truly tempting offer, and I'm horribly sorry to decline, but I'm afraid I have an important matter to attend to.”
Tsukiyo spoke solemnly. She sounded like she really wanted to discuss mysteries with cards with Kuruma.
“An important matter?”
“Yes, I need your key to the safe.”
Kuruma's eyes widened.
“The key to the safe? Why?”
“Because I need the master key.”
Tsukiyo's reply was instantaneous.
“But Detective Kagami turned the combination lock on the safe. It can't be opened, even with the keys Dr. Ichijou and I have.”
“That's fine. As a great detective, I've mastered the art of safe cracking.”
Cracking safes is a skill used by robbers, not detectives, Yuma thought.
“Well... Why do you want to take the master key out of the safe in the first place?”
“For the investigation. In order to uncover the truth of the case and ensure everyone's safety, we need to thoroughly investigate the three bodies and the crime scenes.”
“No, no, that is completely unacceptable!”
Sakyo shouted, standing.
“Why is that?”
Tsukiyo asked, head tilting.
“Isn't it obvious? We put the master key in that safe so that everyone would be safe. If you take it out, the safety of those remaining in their rooms will be compromised.”
“You all will know that I'm the one who took the master key, so if someone is killed in their room tonight, I'll be the prime suspect. Even if I were the culprit, I would never commit a crime under those circumstances.”
“You don't get it, do you? You might be planning to kill us all.”
“If that was the case, I would have killed you now and taken the key without asking.”
Sakyo's lip twitched at the frightening words.
“I-I'm still against it. You say we should expose the truth to ensure our safety, but there's no need for that. After all, the police will rescue us tomorrow.”
“And you think the culprit will politely wait until then?”
“The culprit's motive is revenge for the human experimentation performed in the basement, right? In that case, there shouldn't be any more murders. After all, the three people involved in the experiments are already dead.”
“Unfortunately, that isn't the case. There may be more murders.”
Sakyo stiffened at Tsukiyo's ominous prophecy, an “Eh...?” escaping his lips.
“You think Yuma slipped and fell down the stairs, don't you? That was my first assumption, too. But the truth is, he was pushed.”
Sakyo's eyes shot open. Kuruma leaned forward and asked “Is that true!?”
“Yes... it is.”
Yuma slowly nodded, and Sakyo let out a cry of despair.
“No...”
He covered his face with his hands.
“Yuma was lucky to escape serious injury. But if he'd landed a bit worse, he could have died. That means there's still someone lurking within the Tower who wishes us harm. Until we discover their identity, we can't be sure we're safe.”
Tsukiyo paused for breath.
“That's why I, as a great detective, need to solve this case. Please, give me the key to the safe.”
“But... that's...”
Ignoring the flustered Sakyo, Kuruma stood up and took a keychain from the pocket of his kimono, removing the small key on the end.
“Thank you, Mr. Kuruma.”
Tsukiyo took the key to the safe from his outstretched hand. However, Kuruma didn't let go.
“Ms. Aoi, you have a point. But I'm still not sure you aren't the culprits.”
“As I explained earlier, if we were the culprits...”
“You would have killed us and taken the key. But if your goal wasn't to kill all of us, that would be a different story.”
“What do you mean?”
Tsukiyo asked with cheer, as though she enjoyed this sort of talk.
“You might try to destroy evidence. You killed the three people and your revenge is already complete, but you realized you left important evidence at one of the crime scenes. However, the first and third crime scenes are locked and you can't get in. That's why you need the key to get in and destroy the evidence before the police arrive.”
“I see, what a splendid hypothesis. You're amazing, Mr. Kuruma.”
“Don't you flatter me. Can you deny it?”
“No, it's a difficult theory to deny. But if you suspect it, then there's an easy fix. Surely you've already noticed, sir.”
Kuruma's expression soured at Tsukiyo's provocative words.
“Someone needs to accompany you on your investigation and keep an eye on you to make sure you don't try to dispose of evidence.”
“That's right. And in the current situation, there's probably only one person who can do that.”
Kagami would refuse to let Tsukiyo investigate at all. Sakaizumi was drunk and in shock, and it seemed unlikely that Sakyo or Yumeyomi would agree to go to a crime scene. So... Yuma stared at the profile of the old writer's face.
“It's me,” Kuruma sighed, letting go of the key to the safe. “There's no other way. I'll accompany you. I'll get to see a great detective's investigation in person. This might be a valuable experience.”
“Wait, Mr. Kuruma. What will we do?”
“You can wait here. There are two grown men present. The culprit won't try anything.”
“But... There's a chance Mr. Sakaizumi is the culprit...” Sakyo said, pointing to his drunken form.
“That's fine,” Tsukiyo said. “If there are only two people present and one of them is killed, the other will immediately be declared the culprit. Mr. Sakaizumi won't try anything. Of course, the same applies to you, Mr. Sakyo, so we can leave Mr. Sakaizumi here with peace of mind.”
“B-But, with Mr. Sakaizumi like this, I don't know if the two of us could fight off an assailant...
“If anything happens, just hit that button.”
Kuruma pointed to the fire alarm on the wall nearby.
“When the alarm goes off, everyone will come running. Well then, Ms. Aoi, let's go.”
Leaving behind Sakyo, who appeared to be on the verge of a nervous breakdown, Kuruma headed for the door. Tsukiyo replied “With pleasure, sir,” like a bartender.
Leaving the game room, Yuma and the others arrived in front of the safe in the underground storeroom. Kneeling down, Tsukiyo inserted the keys that Yuma and Kuruma had given her into the keyholes and turned them both at the same time. They heard the faint metallic sound of the lock opening.
Tsukiyo grabbed the lever and tried to turn it. But it didn't budge.
“The combination lock is still secured. Now, Yuma, may I borrow your stethoscope?”
Yuma handed the stethoscope to Tsukiyo, who put it on her ears, placed the resonator against the safe's door, and began to slowly turn the dial.
A few minutes later, Yuma asked “Does it look like it will open?” Tsukiyo glared at him and held her index finger over her lips. Yuma covered his mouth with both hands. In that space, where the only sound was the clickclickclick of Tsukiyo turning the dial, Yuma and Kuruma were extremely bored.
After about thirty minutes, just as Yuma was reaching the limits of his patience, Tsukiyo suddenly removed the stethoscope and took a deep breath.
“No good?”
When he called out to her, Tsukiyo raised one end of her lips and grabbed the handle. The lever, which had previously been immovable, sharply descended. A moment later, the door opened.
“Never underestimate a great detective, Yuma.”
Holding the key marked “Zero” next to her face, Tsukiyo winked at him.