Kaito Arai awoke with the taste of rust in his mouth.
For a few seconds, he didn't move. He kept his eyes closed and listened.
There was no traffic noise. No air conditioner. No distant voices. None of the common city noises that he was used to.
Just the low irregular humming of machinery running too far away to pinpoint. It wasn't loud enough to be comforting, but it was too steady to ignore.
His back pressed against cold stone.
Wait a second... stone?
It felt rough, uneven and odd.
That was the first thing that seemed wrong.
Kaito opened his eyes.
The ceiling was close. Close enough where if he got up too fast, he was bound to hit his head.
Narrow fluorescent strips ran along the edges, embedded directly into the stone, casting a pale, sickly light that didn't flicker.
He pushed himself up onto his elbows.
The corridor stretched in two directions, both disappearing into darkness after about twenty meters. The walls were carved, not poured. Tool marks were visible. There were irregular grooves that caught shadows in ways his eyes didn't like.
"Okay," Kaito muttered. His voice echoed, but not cleanly. The sound bent, as if absorbed and released unevenly.
He stood slowly, testing his balance.
He felt fine.
His pockets were empty except for his phone.
Relief surged, then died immediately.
No service... who would have thought!
The battery was at ninety-eight percent.
That bothered him more than if it had been dead.
He turned in a slow circle, breathing evenly.
Don't assume anything yet.
That was how Kaito survived most situations, not by acting quickly, but by refusing to commit to the wrong explanation.
He took three steps down the left corridor.
After five seconds, he heard footsteps.
He froze.
They weren't approaching. They were… syncing.
Someone else had stopped moving at the same time.
"Hello?" a voice called, farther down the corridor.
It was a male voice. It sounded young but it was also clear that he was nervous.
Kaito didn't answer immediately.
"Is someone there?" the voice said again. "This isn't funny."
Kaito stepped forward again, deliberately slow.
The footsteps resumed.
They met at an intersection.
Four corridors converged, forming a rough cross. The stone here was darker, worn smooth in places, like countless hands had brushed against it over time.
Three other people stood there.
A tall boy with broad shoulders and slick black hair, fists clenched.
A girl with long hair tied into a messy ponytail sat on the ground with her knees pulled to her chest, staring at the wall like it might start talking back.
And the voice belonged to a guy about Kaito's age, thin, with glasses slightly crooked on his face. He looked relieved when he saw another person and immediately more afraid when he realized how many there were.
"Oh," the tall boy said. "Good, more people, that's good."
No one really agreed.
Kaito leaned against the wall and watched.
The tall boy was doing what people always did first: asserting momentum. Moving, speaking, filling the space so silence didn't get ideas.
Although, I gotta admit it's better than pure awkward silence.
"I'm Riku," the boy said. "I don't know where the hell we are, but sitting around isn't going to help. We should pick a direction and go."
The girl on the ground flinched slightly at his raised voice.
The glasses guy nodded too fast. "Yeah. Yeah, that makes sense."
Kaito felt it then.
Assumption.
They already believed that this was something to be beaten by progress.
That belief could kill someone.
"Before that," Kaito said calmly, "does anyone remember how they got here?"
Three heads turned toward him.
Riku frowned. "You think that matters?"
"Yes," Kaito said. "Because if we don't know how we arrived, we don't know what rules we're already breaking."
The glasses guy hesitated. "I was… on the subway. I think. I remember the lights going out."
The girl swallowed. "I was asleep. In my room. I don't remember anything else."
Riku scoffed. "I was walking home. That's it. None of this explains—"
A sound cut him off.
A deep, grinding noise echoed through the corridors, vibrating through the stone under their feet. Although it wasn't sudden, it wound up, like something massive shifting position.
The lights dimmed slightly.
Then text appeared on the wall in front of them, glowing red against the stone.
"WELCOME TO MAZE ZERO"
The girl gasped.
The glasses guy stumbled back. "No. No, no, no—this is fake. This has to be fake!"
Riku stared at the text, jaw tight. "Maze Zero? Like… a game?"
Kaito didn't look at the text for long.
So we are in a maze, huh?
He watched the walls.
The grooves in the stone seemed deeper now. Shadows shifted where there shouldn't have been any light change.
The maze wasn't just displaying information.
It was listening.
New text appeared.
"RULE ONE: THE MAZE RESPONDS TO CHOICE"
"RULE TWO: THE MAZE DOES NOT WARN"
"RULE THREE: THERE IS NO NEUTRAL ACTION"
Silence followed.
"T-That's it?" The girl said.
"No neutral action?" Riku repeated quietly. "That doesn't make sense."
"It does," The glasses guy said quietly.
Kaito looked towards him.
"It means hesitation is a decision," he continued. "So is rushing. So is silence."
The girl hugged her knees tighter. "Are you saying… it knows what we are doing?"
Everybody stayed silent after that.
Riku walked toward one of the corridors branching away from the intersection. About ten meters in, the floor changed texture, subtly. The stone became smoother, almost polished.
He stopped right at the edge.
"Don't step there yet," The glasses guy said.
Riku bristled. "Why not?"
"Because we can't just go where ever we want on impulse."
A sharp click echoed behind them.
They turned.
The corridor they had entered from was gone.
Where there had been an open passage was now a solid stone wall, seamless except for faint tool marks that hadn't been there seconds earlier.
The girl screamed.
Riku swore and ran to the wall, slamming his palms against it. "Hey! HEY!"
Nothing.
The hum beneath their feet changed pitch.
Kaito exhaled slowly.
First rule confirmed.
"We need to move," Riku said, voice tight. "Now."
Kaito shook his head. "We need to move correctly."
"And how do you know what that is?" Riku snapped.
"I don't," Kaito said honestly. "But I know what will make it worse."
The lights flickered again.
More text appeared.
ZONE ONE: THE SPLIT
EXIT REQUIRES SEPARATION
The girl sobbed openly now.
The glasses guy's hands trembled. "Separation? Like… splitting up?"
Riku's eyes hardened. "That's stupid. That's how people die in horror movies."
Kaito felt a cold clarity settle in his chest.
The maze wasn't forcing separation to kill them.
It was forcing separation to see who chose it.
But then again, is it really forcing us? Or is the decision actually in our hands.
"There are four corridors," The glasses guy said. "And four of us."
"No," the girl said desperately. "No, no, no—"
"If we refuse," The glasses guy continued, "the maze will escalate. Not because it's angry. Because it needs data."
Riku turned on him. "You're talking like this thing is alive."
The glasses guy wiped his face. "Whatever, suit yourselves. I'm going."
Kaito looked at him.
The hum deepened.
The walls began to shift.
Not closing in, but rearranging.
Time was running out.
Kaito stepped back toward the intersection.
"For now, I think we should listen to what the maze says."
Riku stared. "Why?"
"Because the maze is watching our reactions," Kaito said. "Not bravery or logic."
The girl looked up at him, eyes red. "What happens if we choose wrong?"
Kaito met her gaze.
"Then the maze learns," he said. "And the next choice becomes worse."
He turned down the corridor he'd inspected earlier, the one with the smooth floor.
As he crossed the threshold, the stone beneath his feet warmed slightly.
He didn't look back.
The corridor curved sharply, cutting off sound and light.
After ten steps, the lights behind him went out.
He was alone.
The hum changed again, satisfied.
Kaito stopped walking.
He pressed his palm against the wall.
The stone vibrated faintly.
"So that's how it is," he murmured.
Kaito had a theory.
The maze didn't care about survival.
It cared about how people justified it.
And if that was true—
Then the most dangerous thing in this place wasn't the walls.
It was the moment when someone decided their reason to live mattered more than someone else's.
The lights ahead turned on.
Kaito took a breath and stepped forward.