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Takuya didn’t mean to find it.
He was just looking for a file. Chuuya had left his office door cracked, which was unusual, but not unheard of—especially after long missions. The place still smelled like cigarettes and rain. Takuya had stepped in only halfway, muttering to himself, scanning the cluttered desk for the signed authorization forms Dazai had been pestering them both for.
He didn’t see the notebook right away. Not until he knocked over a file folder and something dark slipped from between the pages and skidded under the desk. He crouched to retrieve it.
Black leather. Worn edges. Slim and unmarked.
Takuya wasn’t stupid. Chuuya Nakahara didn’t carry notebooks. He carried knives and grudges. But curiosity had teeth, and Takuya’s fingers itched with the temptation of secrets.
He flipped it open.
The first few pages were dated, but not labeled—just descriptions. Clinical, but vivid. “Method 1: The Unbearable Heat.” “Method 3: Silence and Deprivation” Then the more horrific ones: The Mirror Room. Skin Hunger. The Kind One.
Each entry was detailed, disturbingly methodical. Takuya skimmed faster, heart pounding. His mouth went dry. This wasn’t just strategy—it was obsession. Every page was its own self-contained horror.
And then… he heard a click.
He froze.
Slowly, he turned toward the door.
Chuuya stood there. Hair damp from the mist outside. Gloves off. Red coat slung over his shoulder like he had all the time in the world.
“I was wondering where I left that,” Chuuya said softly, stepping inside and closing the door behind him with a click that felt louder than it should have.
“I—” Takuya held up the notebook with shaking fingers. “I didn’t know. I wasn’t trying to—”
“You read it.”
Takuya swallowed hard. “Just a few pages. I thought it was—orders. A report or—”
Chuuya didn’t respond right away. He walked to the desk and set his coat down, stretching his shoulders slowly like he was rolling out tension. Then he looked at the notebook in Takuya’s hand.
“Give it back.”
Takuya did. His fingers brushed Chuuya’s as he handed it over—and something shifted in the air.
Something wrong.
The temperature didn’t change. The light didn’t dim. But Takuya’s ears popped like pressure had just dropped in the room.
“Chuuya—sir—I won’t tell anyone. I swear on—”
“You won’t,” Chuuya agreed. “Because you’re going to help me with something.”
Takuya blinked. “Help you?”
“I need to test something new. You’re the perfect subject. Not too high up to be a problem; not too high up to be noticed. Loyal enough to keep a secret, stupid enough to open a stranger’s notebook.”
Chuuya took a step forward.
Takuya took one back. “Wait—no. You don’t have to—”
“Sit.”
His knees buckled without thought. His body moved without permission. What the hell—?
Chuuya crouched beside him, pulling something from his pocket. A small box. Black. Smooth. Barely the size of a jewelry case.
He opened it.
No wires. No screen. Just a strange shimmer inside—like the air itself was bending around it.
“Method Eleven,” Chuuya said softly, almost like a lullaby. “The Echo Box.”
Takuya stirred on the floor, limbs jerking like a puppet on frayed strings. His body refused to obey him. His lips trembled with the effort of forming words.
“Wh… what is that?” His voice cracked, raw and broken. “What does it… do?”
Chuuya crouched in front of him, gloved fingers loosening around the small, unassuming black device in his hand. It looked like nothing—a smooth, curved box the size of a palm, matte finish, no seams, no buttons. It didn’t hum, didn’t glow. But even before it activated, it felt wrong. Like it had weight beyond mass. Like the air bent around it.
“It records,” Chuuya said, voice hushed, reverent. “Not images. Not sound. Experience. Emotion. Thought. Pain. Every thread of you unraveled and rewoven. One hour’s worth.”
He placed the device gently on the floor between them. “And then it plays it back. On loop. To you. And only you.”
Takuya blinked. Sweat streaked down his temples. “That’s not—”
“Possible?” Chuuya interrupted, tilting his head. A smile flickered across his lips, not unkind—just tired. “You read the notebook. You tell me what’s possible.”
The box pulsed once. A faint, ghostly blue light seeped through its base like a heartbeat under skin.
And then—
Nothing.
No surge. No crackle. No sound.
But the world fell away.
Takuya’s breath caught. His pupils dilated. His chest heaved like he’d been kicked in the ribs.
Because the hallway, the walls, even the light—disappeared. Not in a flash, not like an illusion breaking. It was worse. Subtler. He could still see the room, somewhere in the corner of his mind. But it no longer mattered. It was drowned beneath something deeper—something internal.
Memories rose. Not like film reels. Like tides. Like waves, crashing over his mind, thick and suffocating.
Shame. Terror. Self-hatred.
The moment he first lied to survive. The moment he realized Dazai never blinked at corpses. The way his hands shook when he held the gun that night—and how they stopped shaking the next time. Every face of every person he killed. Every expression—fear, anger, betrayal. How easy it had become to forget them. How proud he’d once been that he could.
And now they were all back.
But not just in thought. In feeling.
His knees buckled. He collapsed sideways onto the floor, shivering violently, eyes wide and vacant.
He smelled blood—his own, theirs. He heard someone sobbing. Was it him? Had it been him all along?
It was like drowning in himself.
“Make it stop,” he rasped. “Please—I’ll forget it all, I swear, I’ll erase the names, I’ll cut out my own tongue, just—please—”
Chuuya didn’t move. His expression didn’t change.
When he finally leaned in, his voice was low and even. “You should’ve just taken the file, Takuya.”
The Echo Box pulsed again.
Takuya’s body arched as the loop hit him like a whipcrack. He screamed—raw, guttural, unrestrained. Not like a man in pain, but a soul cracking open under weight it was never meant to carry.
⸻
Two hours later.
Chuuya emerged from his office in silence. The hallway was dark, washed in the pale gold glow of distant lamps. He rolled his neck until it cracked, then exhaled slowly, like he was coming down from something far colder than fury.
Behind him, the door clicked shut.
Takuya was still inside.
Slumped against the wall, eyes glassy, lips parted. Silent tears stained his cheeks, but he didn’t sob anymore. He didn’t move.
He’d screamed himself hoarse half an hour ago. Then whimpered. Then just breathed—shallow and uneven.
His fingers twitched now and then, as if reaching for something that wasn’t there. Occasionally, a tremor ran through him, like a shiver through a broken circuit.
Chuuya paused. Just long enough to glance back once, unreadable.
Takuya didn’t look up. Didn’t seem to register his presence at all.
He wasn’t broken in the physical sense. No blood. No bruises. But something inside him had shattered—so deeply, so intimately, it couldn’t even be named. Because the Echo Box didn’t leave scars.
It left imprints.
It blurred the line between memory and identity. Until you couldn’t tell if the pain you felt was a memory or just the shape of who you’d become.
He would forget the notebook. That much was certain. He’d forget what he wasn’t supposed to know. He wouldn’t remember the loop.
But he would feel it. For weeks. Months. Maybe forever.
Like a splinter under the skin of his soul.
Chuuya adjusted the collar of his coat and slipped the black notebook back into his inner pocket.
Some secrets weren’t kept.
They were enforced.