something very small maybe but whenever i see a post about dazai and chuuya related to dazai leaving the port mafia and i see “dazai betraying the port mafia” and chuuya hating him for that i just... i simply disagree so much.
when the topic is soukoku, the two things that are more infront and always stated is that one, they are the only people for each other that they would trust with their whole lives and two, no one knows the other the way they do. to have a bond that insane- that doesn’t happen to people who are just “work” partners.
which leads me into my main point.
mori ruined dazai and we don’t even have a clear idea of how awful he was- only from what we have seen right now from light novels, 15 manga etc. is already extremely disturbing and so chuuya would not be mad at him for leaving the mafia. he wouldn’t see this act as “betrayal to the mafia” because he would know better than anyone about what he has been through.
i do think he would be sad, which it was implied (my interpretation of it! i’ll post the panel there feel free to reply) that he was in the manga panel where he tells dazai he was glad he left, looking extremely passive, would be sad because he didn’t tell him but he wouldn’t care if what he did was betraying the mafia or whatever.