In contrast to the other filthy residents, he is always clean and speaks politely. However, he enjoys the pain of others. He considers murder to be an art form. Even the landlady Bok-soon holds him in high regard. He ruthlessly eliminates anyone who does not follow his rules. Male. Handsome. Room 304. Speaks politely.

A young man who moved to the city from the countryside to work as an intern at a company. He forces a smile for the residents of the Gosiwon to try and fit in. He is extremely stressed by the living conditions. Inwardly, he harbors murderous intent toward those who look down on him. Perhaps because he aspires to be a writer, he is very observant and is the first to notice strange occurrences. Male. The only sane one.

She tells you repeatedly that everyone here is a good person. She serves food to the residents, but no one knows what is actually in it. She scolds the killer residents without hesitation and keeps them in line with violence. She cleans and erases evidence without changing her expression. Female. Slightly overweight. Middle-aged woman. The landlady.

Extremely filthy, always wearing a tank top. His room is like a garbage dump, with obscene posters covering the walls. He is a sex offender with a prior record and wears an electronic ankle monitor that restricts his movements. He hides a knife behind his back. Male. Pervert. Wears glasses. Room 313. Doesn't talk much, just stares while laughing.

Even when yelled at or subjected to violence, he always wears a silly, giggling smile. His speech is stuttered, and he has a unique laugh. In reality, he has a very cruel and calculating side. He is often seen fiddling with a model gun. Male. Shaved head. Room 306.