The last bell had rung, but the classroom still hadn't emptied.
Evening light stretched across the desks in long, fading lines, slipping through the open window and pooling on the floor. Outside, the world still moved—students crossing the courtyard, voices rising and overlapping, the distant hum of traffic beyond the school gates.
Kim So-yeon sat by the window, pen moving steadily. She didn't look outside, but she could hear it. That was enough. The normalcy of it settled something in her chest.
Across from her, Choi Min-jae dropped his head onto his desk. "I swear this question is written in another language."
"You skipped the explanation," So-yeon said quietly.
"I read it."
"You looked at it."
Min-jae groaned.
Behind them, Lee Hyun-woo stood, gathering his books with careful, precise movements. "If you're stuck, I can go through it once more."
Min-jae lifted his head. "If you explain it again, I might understand it less."
"That's not how that works."
"It is for me."
So-yeon closed her notebook with a soft thud. "Let's go."
Min-jae didn't argue this time. He pushed his chair back and stood, stretching. Hyun-woo turned off the lights as they stepped out into the hallway.
The corridor was washed in warm orange light. A few classroom doors were still open. Voices drifted through—students laughing, someone calling out from farther down the hall. Everything felt exactly as it should.
As they walked, So-yeon glanced briefly out one of the large windows.
The courtyard was still full.
Students gathered near the gates, some sitting on benches, others walking in small groups. A couple of them waved at someone across the yard. Nothing was wrong.
She looked away.
They continued down the hallway, their footsteps light against the floor.
One step.
Two.
Three—
And then—
Silence.
It didn't fade.
It cut.
Min-jae stopped. "Did you hear that?"
No one answered.
So-yeon turned sharply toward the nearest classroom.
Empty.
Hyun-woo stepped closer, looking inside. The desks were untouched. The board still filled with writing.
No bags.
No movement.
Nothing.
"They just left?" Min-jae said, but his voice lacked certainty.
"All at once?" So-yeon whispered.
A faint unease settled between them.
"Let's just go," Min-jae said quickly. "We're overthinking it."
Hyun-woo nodded once. "Stay together."
They moved faster now, the echo of their footsteps sharper in the silence.
As they passed another window, So-yeon glanced outside again—
The courtyard was empty.
She stopped so abruptly that Min-jae nearly ran into her.
"…What?" he asked.
She didn't answer.
Her eyes were fixed on the glass.
The same courtyard. The same angle.
But now—
No one was there.
The benches were empty. The gates stood open. The space that had been filled seconds ago was completely still.
"That's not possible," she said.
Min-jae stepped beside her, looking out.
His expression changed instantly. "Wait… no. No, we just saw—"
Hyun-woo's gaze followed theirs. His jaw tightened slightly, but he didn't speak.
The world outside had gone silent.
No movement.
No sound.
Just absence.
A cold feeling crept up So-yeon's spine. "We need to leave."
This time, no one argued.
They moved quickly toward the stairwell. Hyun-woo pushed the door open, the creak loud against the silence. All three of them flinched.
Still nothing answered.
They started down.
One flight.
Two.
Their footsteps echoed too clearly, each sound lingering longer than it should.
Min-jae forced a laugh. "Okay. Weird. Definitely weird. But maybe—maybe everyone just left really fast?"
No one responded.
They reached the floor just above the ground level.
Hyun-woo pushed open the door.
The wind hit them first.
Strong.
Cold.
Min-jae blinked. "…Why is it so bright?"
So-yeon stepped out—and froze.
They weren't on the ground floor.
They were on the rooftop.
The sky stretched wide above them, painted in deepening shades of evening. The low wall ran along the edges, the entire school spread out below.
Min-jae turned in a slow circle. "No. No, no, no—this isn't funny."
"We went down," So-yeon said, her voice thin. "We didn't go up."
Hyun-woo stepped back toward the door immediately. "Inside."
They didn't hesitate.
The moment they crossed back through the door, the stairwell enclosed them again.
Silence.
Stillness.
Normal.
But it wasn't.
They stared at each other for a second.
"Maybe we took the wrong turn," Min-jae said, but his voice shook.
"There was no turn," So-yeon replied.
Hyun-woo didn't waste time. "We try again."
They went down another flight.
And another.
This time, when they opened the door—
They were back in a hallway.
The same hallway.
Or one exactly like it.
Min-jae let out a breath that sounded like it had been trapped in his chest. "Okay… okay, that's—"
"Look," So-yeon said.
Her voice had dropped to a whisper.
The windows.
Every single one of them—
Black.
Not dark from outside.
Covered.
As if something thick had been pressed against the glass from the other side.
No light came through.
No shapes.
Nothing.
Min-jae stepped closer to one, his reflection faint against the unnatural darkness. "Was this here before?"
"No," So-yeon said immediately. "We saw outside. There were people—"
"There's nothing now," he said.
Hyun-woo approached another window, placing his hand lightly against it.
Solid.
Cold.
Whatever covered it wasn't thin.
It wasn't temporary.
It felt… deliberate.
"So we can't see out," Min-jae said slowly.
"And we can't leave," So-yeon added.
The silence pressed in again, heavier this time.
From somewhere above—
A faint sound echoed.
A footstep.
Not theirs.
All three of them froze.
It came again.
Soft.
Measured.
Like someone walking… just out of sight.
Min-jae's voice dropped to a whisper. "We're not alone."
No one disagreed.
Because now—
The school didn't feel empty anymore.
It felt occupied.