I think he blames himself because he as blamed by Yuma before when he was sexually assaulted at first. When you are sa and someone blames you, even if they retract their statement and say it’s not your fault in the end you can’t help but feel you’re the one in the wrong. It’s sad.
Him saying he deserved it after getting punched in the face uhhhhhh no sweetie you don't. You didn't cheat, blondie sexually assaulted you twice