So it's Jaeha's fault that Yoseob is like that? Looking at the recent chapters, I think it...

They were all kids. If you don't tell them what they think is right is actually wrong, they will keep doing it.... I think this all goes back to those abusive parents of yoseob and jeaha being bullied. Taeho also felt hated by his brother. In the end if the adult paid more attention maybe it could have been avoid éd （￣へ￣）Sad.