Chiaki had lied after all.
The man surrounded by frost left the room, leaving Chiaki sitting there in thought.
What Chiaki said was half-true and half-false. Lin believed the first half—up to the point where she was stalking him—because she even knew his route home and the fact that he hadn't left his house except for school for nearly a month.
But the latter half was just nonsense.
Lin had also told her about the "last time," which was also half-true, omitting the fact that she had eventually been shot and killed for him.
The rest would be up to her own judgment.
As for the others—was it necessary to inform them one by one?
There was no need.
Because soon, it would all be over.
"Lin, Dr. Mobius said..."
Prometheus found Lin on the deck. As she walked through the door, she saw Lin checking his equipment and weapons. He was fully armed, looking as if he were ready to deploy on a mission.
"No Ritalin. I know," Lin interrupted Prometheus. He slammed a loaded magazine back into his pistol but didn't holster it. Holding it in his hand, he raised his head and pointed his finger toward the distant horizon.
"Prometheus, do you know what lies across the sea?"
Lin tone was more excited than ever before. He was like a scholar seeking knowledge, eager for an answer.
Prometheus answered in confusion, "The continent of Mu?"
"..." Lin shook his head. He turned back, his dark eyes behind the helmet staring at her intently. "The answer is: nothing."
"..."
"If it were Prometheus, she wouldn't have said 'the continent of Mu' with a questioning tone. No matter how personified her personality is, she is still an AI governed by rigorous logic. And after hearing my answer, she should have asked me why, rather than remaining silent—because she is still learning how to possess human ways of thinking."
"...What are you talking about?"
Prometheus suddenly took a step back. A gaze more terrifying and sharp than a blade rested on her face. After taking that step back, she realized she had exposed herself.
An AI would not feel fear.
"You made three mistakes. First: you kill Vil-V every time. Besides Mei and me, she is the one who understands Prometheus best. Her erratic thinking ensures that once I give her information, she can quickly find the root of the problem. Thus, this 'unchanging variable' in a sea of change became the breakthrough for my thoughts."
"That's why I asked you to protect Vil-V this time. You are the only thing that hasn't changed throughout these 'variations.'"
If Vil-V were killed, it would arouse Lin suspicion. But not killing her would confirm Lin guess even more. The only solution was to find a way to attack Vil-V without killing her, while pretending to protect her.
Was it because she was the one who notified Lin every time that she had aroused his suspicion?
Giving her no room to think, Lin held up a second finger. His voice grew heavier. "Second: you chose to disguise yourself as Prometheus. Prometheus appears by my side frequently; if she vanished, it would inevitably cause me suspicion. But out of all the 'robots' that disappeared, Prometheus is the only one left. Don't you find that strange?"
"Even though you set up various excuses—like Prometheus No. 2 being under maintenance, or Armed Puppets undergoing Soul Steel upgrades... it couldn't entirely erase my suspicion. Moreover, you are merely imitating Prometheus through my memories. Every action you took felt like a strong violation of her character to me."
Would Prometheus cry and tremble for Vil-V? Perhaps. But she couldn't express her emotions with such humanized vocabulary.
At the "end" of the last time, Prometheus act of stepping out to explain that he was the mastermind was also something the original Prometheus would never do. That was entirely the behavior of a killer flaunting their achievement and trying to crush his mental defenses.
As for why she did that...
"Third."
Lin held up a third finger, calmly gazing at the now-silent Prometheus.
"Those 'prompts' of yours in my ear... they were real..."
"How annoying."
Prometheus face suddenly twisted. The shame and anger of being exposed flared up, but half a second later, she returned to a robotic blankness, as if she didn't understand a single word Lin said.
"When I first entered this place, you intentionally used fragmented speech to remind me that my environment had changed, keeping my nerves strained and making me look for anything unusual. The only complete sentence was 'Don't believe Lin.'"
"That sentence has two meanings. One is 'Don't believe, Lin'—a pure warning to be careful of my surroundings. Before I experienced the second loop, I naturally understood it in that first sense."
"That way, you could make me exert all my effort to doubt everyone around me, racking my brain to figure out who the mastermind was, setting the stage for the second meaning."
"And the second meaning, 'Don't believe Lin,' was meant to completely destroy my mental defenses. After I doubted my friends and learned the 'truth' that I was the killer, I would go mad, kill those I cherished, and destroy the hope of humanity. At that point, my consciousness would be on the brink of a total collapse."
"By then, even if my consciousness hadn't been eroded, I would have become indistinguishable from someone who was."
Lin analyzed coldly. His vulnerability, collapse, and confusion from the previous two times were now gone. His logic was crushing the nerves of the culprit before him.
Yes—he even looked more superior now.
"With the power to do this, you could naturally kill everyone at the headquarters. After all, this is your world. Aside from my consciousness, you can kill everyone. That is also why I never witnessed your 'death' either time."
"...Where is the evidence?"
"..."
"You say I am the killer. Where is the evidence?"
Lin snapped his fingers.
He had learned this from Vil-V. It meant...
The show begins.
"Why do I need evidence?"
"Without evidence—"
"I don't need to convince you. There is no one here I need to convince. I don't need to explain to anyone else why you are the traitor or what your true face is." Lin exhaled a breath of cold air. "And the flaws in your actions... there are actually many more. For example, the database theft. You discovered that no one in Fire Moth had information about the WM series in their memories. After all, those were top-secret files kept by the deceased Fire Moth high command."
So, when Lin destroyed the data, he had already discovered that it was exactly what he imagined the WM series data to be.
It was his "memory."
"When did you start doubting me?"
"From the very beginning." Lin said cruelly. "From the moment you first smashed that plate—that rookie mistake that Prometheus would never make."