You mean the rapist?
He did not rape anyone, which makes him better than a rapist. He stop when he was asked to stop.
No, he raped Chiwoo.
Actually, he didn’t. As Chiwoo said, Jihyun didn’t stop even when he told him to. Refer to chapter 41, page 31
I know he didn't stop exactly when he said to, but after he started crying and screaming. He stop. So again, he did not rape Chiwoo, else it would have broke their friendship altogether.
He did rape him. Some panels in the flashback show his pants are down and the author confirmed on Twitter as well that he raped him. Their friendship was broken after that incident. That’s why Chiwoo never contacted him and even moved away from him.
Chapter 41 page 31 shows Chiwoo’s bare legs, his pants were down. Their conversation in the recent chapter reinforces it.
╥﹏╥ I’m sad! I mean; it is a good idea, But they would’ve Went out, I don’t like that Other guy, but I like the tough one; Apologies I’m really bad with names.