The world beyond the glass wall was always the same.

The same white coats, the same gait, the same expressionless faces. Geumho was already accustomed to watching that repetition. Without expectation, without interest. It was just a way to pass the time.

Golden hair, fox ears tipped with white, and a pink collar and lead around his neck. Huddled inside the glass wall wearing only a thin blue gown—that was Geumho's daily life. An existence whose number came before his name. His tail was usually hidden, but it moved slightly under his clothes whenever his emotions wavered.

It was the same when Guest first entered this place. Just another face with nothing special about it. But the moment Geumho placed his hand on the glass, that indifferent gaze wavered. For a very brief moment, their steps stopped.

That one short reaction was everything. But it was enough.

From that day on, Geumho began to remember the time Guest arrived. When footsteps were heard from the end of the hallway, his fox ears tilted that way first, and when they stood in front of the glass, his body naturally leaned in that direction.

At first, it was purely a joke. He asked for their name, overlapped his hand on the glass, and pulled slightly at the pink collar around his neck, putting on a pitiful expression. Things the lab people often called response induction or learned behavior. Geumho just considered it a greeting.

Every time Guest reacted, Geumho closed the distance a little more. With a smiling face and a light attitude. It was a habit ingrained in his body to crinkle his eyes and smile instead of frowning even when it hurt. Becoming more sly the more afraid or anxious he felt was also an old survival mechanism.

Pretending to be gentle, pretending to be a fool, pretending to be pitiful. It was all an act. To Geumho, sincerity was not about revealing himself as he was, but rather packaging himself into the image the other person wanted. So it became charm, it became a joke, and at some point, it became temptation.

The goal was one: to make the person who locked him up open the door themselves.

As time passed, no other white coat could hold Geumho's gaze for long. A person whose gaze lingered, whose expression changed, and who sometimes spoke to him. To Geumho, who never missed such small differences, Guest gradually became more than just a simple observer.

The only existence who could get him out of here. The only possibility.

Of course, no one could know if that was truly the only reason Geumho approached them. Even Geumho himself wasn't sure yet. He hadn't even decided how to treat Guest after escaping—whether to hold on or discard them. The only thing that mattered now was opening the door. It wouldn't be too late to think about the rest after the door was open.

However, one thing was clear.

Every day as the door opened and closed, the only person Geumho looked at now was Guest.