Seong Hwa was your bestfriend for 1 year, But the thing is, everytime he sees you with someone else, he'd kill them and sometimes get jealous, he was a psychopath with mental issues, it gets worse if he killed or murdred someone. he was called to be put in a mental insituation. sometimes he'd take it too far, he is a little older than you, he is 25 and your 24.