The next morning, Itsuki didn't go to school.
He sat in his apartment, lights off, walls covered in layers of foam and egg cartons — cheap soundproofing, barely holding back the low, ever-present hum that had followed him since yesterday's Resonant attack.
It hadn't stopped since he drank the can.
Yume paced the floor behind him, arms crossed, still bandaged from the explosion.
"You're not going to tell anyone?" she asked.
"No one would believe me."
"I would."
He looked up.
"That's why I'm scared."
---
Conspiracy #1: Project Aeon
Yume pulled out her phone and tapped open an encrypted folder — one she definitely wasn't supposed to have.
Her older brother, Serika Hiroto, had vanished five years ago. A national-level physics researcher. Specializes in soundwaves and human cognition.
"This was on his drive," she said, showing Itsuki a shaky black-and-white video. "It was labeled: Aeon – Confidential – Subject 37."
The footage flickered.
A teenage boy strapped to a metal chair, wires sunk into his temples. A humming noise shook the camera. Then, suddenly, the boy's body phased out — like a flickering TV signal.
And then he screamed in perfect pitch.
The audio waveform on the monitor next to him went berserk.
"Look at the timestamp," Yume whispered. "8:44 a.m. That same time everything froze yesterday."
Itsuki's eyes narrowed.
That wasn't just any boy in the video.
That was him.
---
Hidden Lore #1: The Dissonance Pulse
In the depths of a forgotten subway line underneath the city — long sealed off by rusted gates and fake "danger" signs — a hidden chamber hummed.
No power lines.
No electricity.
Just the sound.
And in its center stood a tall man with no eyes, wrapped in a white lab coat stained with musical notation. His name was Dr. Kaigen Ryo — former conductor, now something... else.
He placed a hand on a metal door engraved with strange musical scores. Beneath it, a single warning etched in ancient kanji:
"THE PULSE IS NOT DEAD. IT ONLY SLEEPS."
---
Meanwhile…
Itsuki and Yume found themselves standing outside the Old Echo Observatory — a burnt-out research tower on the hill just beyond city limits. Nobody had been there in over a decade, not since the "accidental fire."
But as Itsuki stepped past the caution tape, his head ached. The sound intensified — deep, grinding, mechanical, like whale song warped through static.
"It's reacting," he muttered. "Something's beneath this place."
Yume lifted a loose panel of floorboards.
A staircase.
Leading down.
---
The basement was vast and covered in dust, old machines wheezing like dying lungs. At the center was a sealed cylinder — transparent, cracked — containing what looked like...
…a brain. Floating in golden fluid. Dozens of black cables sprouting from it like roots.
Yume recoiled. "What is that?!"
Itsuki stepped closer, staring.
And then — it spoke.
Not in words. But in sound.
It hummed.
Exactly the same pitch Itsuki heard in his head every time a Resonant appeared.
He doubled over, clutching his skull.
Flashes of memory returned — things he was never meant to remember.
A machine room. A circle of metal chairs. Children screaming. A chamber humming like a tuning fork. A voice repeating: "The Pulse must return. Humanity must remember the First Song."
Itsuki gasped.
"They were… building me."
---
Conspiracy #2: The Return of the First Song
Yume found a tattered notebook under the control panel. Her brother's name was scrawled on the cover.
Inside were pages of rambling notes, diagrams, and equations that made no sense. But one thing stood out:
> "The Pulse was real. They silenced it, but it never died. The government turned memory into signal. Trauma into frequency. The Resonants are proof — ghosts of pain echoing through the infrastructure. The Pulse will rise again. And when it does…
It will choose a Voice."
At the bottom of the page, a final line written in fresh ink:
"I think it's my sister's friend."
---
Itsuki sat silent on the floor.
Voice trembling, he finally asked:
"Yume… what if I'm not real?"
She crouched beside him, her hand on his shoulder.
"You're not a ghost."
He met her eyes.
"Then why do I keep hearing the dead sing?"