Totally Agree !
Fuck Sumi tbh . In the last chapter where he was like , " uhh my brother only wants me to safely come back so I can take the family business off of his hands " , like no stfu you lil shit . He totally didn't deserve his younger brother's love and concern . If you can't appreciate something , then you don't deserve it .
Btw , by " you " , I was referring to Sumi not actually you . (●'◡'●)ノ
I felt sorry for him and excuse his INITIAL bad attitude (he got A LOT better later and even got a serious job...) as it was clearly just angst about being raped and about losing his first love, Oomiya. He got rebellious because of the rape, it SHOWS this, his father blew up on him because he thought Sumi attacked a random guy and was going to put him in a psychiatric hospital... He got raped, thought he saw the guy and attacked him to check if it was him, stopped when he saw it wasn't and then was blamed and had to leave the house... Then Oomiya stopped seeing him... Of course he had a bad attitude... And then just now he found out Oomiya got married.
Tbh I was rooting for Sumi... I felt sorry for him