The city was quieter on Thursdays.
Aiko always noticed it most after dark. Less traffic. Fewer trains. Even the neighborhood dogs seemed to bark less. The apartment buzzed faintly with electricity—the old kind, the kind you felt in the walls and behind your teeth.
She stood brushing her teeth again, this time barefoot in the living room, scrolling through the school's group chat.
Mari was arguing about meeting up over the weekend for the dungeon project. Kaoru was ignoring her as usual. Someone else posted a rift meme.
Aiko stared at it longer than she should've: a cartoon of a monster coming out of a convenience store freezer, holding a popsicle and looking confused.
She forced a laugh.
Behind her, the bathroom door opened.
Kaito stepped out, towel around his neck, wet hair sticking to his forehead.
"Did I use your shampoo?" he asked.
She looked up. "Yeah. But I forgive you."
He nodded and walked past.
The hallway light flickered as he did.
That night, Kaito woke up with a sharp, sudden breath.
Not because of a dream.
Because something had shifted inside him.
He sat up in bed, blinking into the dark. The ceiling was still. The moonlight slanted across his desk. But there was a weight in his chest—warm, low, almost like a second heartbeat. Not painful. Not even physical.
Just… present.
His hand moved on its own.
He raised his right arm, palm up. The marks on his wrist glowed faintly again—but this time, they pulsed in a rhythm. Like a signal waiting to be received.
Then, for the first time:
A voice—not from outside, but somewhere behind his ears—spoke.
Not loud.
Not robotic.
Just precise.
[ SYSTEM RECOGNITION: SUCCESSFUL. ][ USER IDENTIFIED: ??? ][ RECONCILIATION ERROR. IDENTITY FRAGMENTATION DETECTED. ]
[ INITIATING PARTIAL AWAKENING… ]
[ SYSTEM CORE IMPRINT… INCOMPLETE. ][ BEGINNING BASELINE CALIBRATION. ]
His breath caught.
Light coiled around his fingertips, then vanished like mist.
Then came the pain—not like a wound, but a sudden vertigo. His head swam. Images flickered in his mind: stairs leading downward, glowing stones, a low humming sound too deep to be heard. Then gone.
Kaito doubled over, gasping.
The system fell silent.
When he opened his eyes, something new hung in the corner of his vision. Not real. Not physical.
A faint, translucent shape. A word.
[ HOLLOW NODE: STABILIZING… ]
And underneath it:
[ 0 / 1 CORE SIGNATURES LOCATED ]
He blinked. The text remained.
When he turned his head, it followed.
Like a ghost just outside his reach.
He stood shakily and made his way to the bathroom.
The mirror was dark. He didn't turn on the light.
His reflection stared back—same face, same blank expression.
But the marks on his arm had changed.
They'd spread.
Up his wrist. Toward his elbow.
Like veins of glowing ink stitched under skin.
He touched the glass.
His reflection didn't move.
The next morning, Kaito sat at the table, staring into a bowl of plain rice.
Aiko sipped coffee across from him, watching him through narrowed eyes.
"You okay?"
He nodded.
"You look pale."
He nodded again.
"You slept, right?"
No answer.
She set the mug down. "You had another weird dream, didn't you."
"No," he said.
She leaned forward slightly. "Then what?"
He didn't speak.
Didn't know how to.
If he said something like the system spoke to me, she'd ask what that meant. And he wasn't sure he could explain it—especially not to someone who still expected him to be her brother.
Instead, he said, "The microwave's broken again."
He wandered outside around noon.
The neighborhood was uneven—old stairwells, cracked concrete, small rooftop gardens clinging to rusted railings. A cat watched him from a fence post. A drone passed overhead, scanning with its slow, whirring pulse.
As he walked past the corner where the vending machine sat, the screen glitched.
Just for a second.
Not much.
But enough.
He turned.
The screen flickered. Then stopped.
Aiko's favorite drink—peach soda—displayed in the slot window even though she hadn't bought one today.
He reached forward and pressed the button.
The machine groaned. Whirred.
Then, with a low thunk, the can dropped.
Free.
He didn't take it.
Just stared.
Back at the apartment, Aiko found a small sticky note on the fridge.
Kaito's handwriting was stiff but neat.
"Went walking. Be back by 2.""Microwave's still weird."
She stared at it, then checked the time.
2:17.
The microwave blinked 88:88.
In the alley behind the building, Kaito sat on a crate, watching ants carry crumbs across a crack in the pavement.
The HUD—the floating words—hadn't disappeared. They faded when he focused on something else but returned the moment he relaxed.
[ HOLLOW NODE: STABILIZING… ][ WARNING: NO CORE ANCHOR DETECTED ]
He didn't know what a "core anchor" was.
He didn't know what a "hollow node" was, either.
He only knew one thing:
The system never asked who he was.
It just accepted him.
Without proof. Without a scan. Without a name.
And that, somehow, made him feel even less real.
Later that night, Aiko came home to find Kaito on the balcony, staring at the sky.
She walked up beside him. "What are you looking at?"
"Nothing."
"The stars?"
"No."
She leaned on the railing. "You ever wonder how far the system reaches?"
He didn't answer.
"Some people say it's not human-made. That it's not even alien. That it's something that came from the dungeons, like the monsters."
Kaito tilted his head. "Do you believe that?"
"I don't know. But it feels like it knows things it shouldn't."
He glanced at her, quiet.
She added, "You've been acting weird again."
He opened his mouth. Then closed it.
"I think I'm changing," he said finally.
"Yeah," she said, softly. "I know."