The first thing Ren noticed was the sound of the rain.
Not the soft, rhythmic kind, but the heavy, urgent slap of water against pavement, windows, and rooftops — the type that sounded like the sky had lost something and was crying too hard to find it. He sat up, heart thudding in his chest like a war drum, and looked around. The room was dim, lit only by the flickering neon sign outside his apartment window that read, Soba & Spirits.
He knew that sign. He'd spent years looking at it, half-drunk, half-lonely.
He was home.
He was alive.
That wasn't right.
Ren's hand flew to his chest — no blood. No wound. But he remembered it. The blade, thin and cold, piercing just below his ribs in the alley behind the library. He remembered the pain. The soft, almost apologetic voice of his killer: "I'm sorry, Ren. You were never supposed to remember."
But he had.
And now he was back.
He stumbled to his feet and clawed at his phone on the table. The screen flickered on. Tuesday, March 11th.
His breath caught. That was impossible.
He died on March 21st.
A soft chime echoed in the room.
[System Tsuki has been installed.]
A translucent screen flickered before him, white letters floating in a sea of midnight blue. Elegant, clean — almost… sterile.
Welcome, Ren Ichiro.
System Tsuki active.
Ren blinked. "A system?"
This was like something out of the RPGs he used to binge when he was younger — the isekai stories with overpowered protagonists, ridiculous stats, and god-like powers. Maybe this was it. Maybe this was how he survived.
Another line appeared.
Assassination in 10 days.
That was it.
No map. No skills. No advice.
Ren waited.
Nothing happened.
"…Do I get powers?" he asked, his voice cracking with the question.
No.
Ren stared. "Then what do you do?"
The system paused.
[Observation Only.]
A beat.
Tsuki does not interfere.
He almost laughed. "Of course. A useless system. I get you."
Another chime.
Correction: Not useless. Watching.
The screen disappeared with a shimmer, like moonlight being swallowed by shadow. And in that moment, Ren understood something deeply unnerving.
He wasn't guided.
He was watched.
At school, things were the same. Too the same. Ren moved through the hallways of Tsukigawa High with the sick certainty of déjà vu sharpening each footstep. The teacher in Room 2A was still humming that same off-key folk tune. The coffee machine in the faculty lounge was still broken. Even Yuki Arisawa's notebook still fell from her locker at exactly 8:13 AM.
He caught it this time. A ripple in the current.
"Thank you," she said, brushing her hair behind her ear — the same shy smile he remembered. She was beautiful in a quiet way, like a secret too delicate to speak aloud.
In another life — ten days from now — he would never get to say goodbye to her.
"You dropped this," he said, handing her the notebook.
"You're… Ren, right?"
Her eyes lingered a second too long. The softest thread of familiarity flickered in her gaze.
"Yes," he said. "And I think I need your help."
That wasn't part of the script.
Later that night, Tsuki returned.
You are deviating.
"Good," Ren said aloud, alone in the dark.
Deviation increases probability of alternate death.
Ren looked out the window. The rain had stopped, but the clouds hung heavy, like the world was still deciding if it was safe to breathe again.
"If someone's going to kill me," he whispered, "I'd at least like to know why."
Tsuki does not provide answers.
Ren smiled thinly. "No. But maybe she will."
He looked at his phone, where Yuki's number — newly added — pulsed like a soft heartbeat.
Ten days.
Ten days to unravel the truth.
Ten days to stop a blade he couldn't see.
Ten days to remember why someone he trusted had whispered an apology as they killed him.
And somewhere in the shadows of those ten days,
a silent system watched.
And did nothing.