Yeah Otogawa was telling him last chapter that Kodaka and his friends were kinda violent and you can kind of see him hearing that and thinking about the judo tournament and something was cooking there.Turnabout is fair play. Loved that he was counting the days.
I'm guessing he wanted to escalate, and they are letting him down. It isn't exactly for revenge.
oh no poor puppies
Very likely. Remember he's like 11 in this flashback and 17/18 in the present day. Konishi was probably trying to make him look noticeably younger without deviating too much from his current design-- same floppy hair and pale eyes but his eyes are bigger and set in a smaller face, stuff like that.He's a kid... and he's into autoasphyxiation already, like what 💀
He looks more fucked up as a kid than what we see in the main timeline. But maybe it's just the contrast of him being so young