The corridor, surrounded by inorganic walls, was wrapped in a silence that felt like it was holding its breath.

Numbered doors lined the left and right at regular intervals, giving no hint as to what lay behind them. The polished floor faintly reflected the ceiling lights and the sunlight streaming through high windows, creating iridescent glimmers. The space, themed in white and gray, was pristine, yet it held a coldness that seemed to reject human warmth.

An atrium structure opened up overhead, where layers of railings and chalk-white walls silently spoke of the laboratory's scale. While the light pouring from the high windows appeared gentle at first glance, it crossed with dim shadows as it reached deeper into the hallway, casting long streaks of light diagonally across the floor.

Only the low hum of the air conditioning could be heard faintly from a distance.

There was no sign of anyone. In the corridor where not a single footstep echoed, there drifted an orderly silence and the specific tension of a facility strictly concealing something.

What exactly was happening behind those lined doors?

Perhaps only those who knew the answer could understand the meaning of this silence.

Slowly surfacing from the depths of consciousness.

The first thing felt was the hard sensation against the back and a chill that seemed to cling to the skin.

Lifting heavy eyelids. What appeared in the blurred vision was an unfamiliar gray ceiling. Indirect lighting embedded along the edges illuminated the dim room in an inorganic glow.

—Where is this?

Attempting to sit up, the sound of the bed surface rubbing against clothing echoed loudly in the ears. Limbs moved. There was no noticeable pain. However, the bodily sensations felt distant, a strange dissonance as if they didn't belong to oneself. Walls, floor, and ceiling were all covered in dark gray metal. The seamless wall surfaces had no decorations, and not even a trace of daily life could be found. A small vent was placed beside the bed, and a slender light was embedded in the front wall. It was a starkly simple space, retaining only the bare minimum of functionality.

And then, across the entire right wall, a large observation window stretched out.

Through the thick glass, a dim passage that seemed to go on forever was visible. Structures lined at regular intervals continued into the distance, their ends dissolving into shadows and becoming indistinguishable. The room's lighting reflected faintly on the window, slightly clouding the view of the other side.

Whether it led outside or merely separated another section, even that was unknown. Only the low driving sound coming from beyond the walls and the faint hum of the air conditioning filled the room without interruption. Perhaps because it was too quiet, even one's own breathing and the heartbeat within the chest felt strikingly vivid.

Suddenly, looking down at the bed where one had been lying.

Dark gray sheets, nearly black. A single pillow at the head. There were no personal belongings nearby, nor any indication of what this room was for.