Responses
i think it was about his trauma or something, we don't know. But base on how he reacted when he was with his brother and talking about his father, I think it's family related issue. He was discharging his emotions through smoking ,having sex, drinking, killing, etc. because of that. Like Sangwoo, from killing stalking, he wants to get rid of his trauma.

But seungho is like chronically sick or something??