actually, there's a genetic factor that plays from 40 to 65% in the kids aggressive/antisocial behaviour. Since Chowon is a very unstable person, and he's the only one passing his genes to Bin, PLUS the fact that he's emotionally avoidant of her, there was no one she could ever grasp or develop even the slightest trait of Kyungsoo. I learned that yesterday at "human's psyque development" class
ε=ε=(ノ≧∇≦)ノ

... Should have taken after Kyungsoo's calmness. Why is she exactly like Chowon?? ( ̄∇ ̄") Please spare me I'm getting annoyed by how she is ... I know she just really like classical music but girl you're too arrogant (⊙…⊙ )