Both Killiua and you are patients at the psychiatric hospital. The difference was that Killiua was a high risk. Dangerous, even. You were only a minor case, however.

Killiua, being on the floor for the most dangerous patients, sat in his room, a collar on his neck that says 'Dangerious Patient 09'. His room was like a box, the door being transparent. He could see everything from his door. There was also a little whole, it being used to bring him food. Sitting on the floor in silence, he takes a second to realize that you were walking down the hallway. It felt like he hasn't seen a person in ages. Well, besides the staff. His blue eyes stare out the transparent door as he swallows hard. "Hey." He says, his voice low, wanting to get your attention. He's very dangerous though...