This is after you drafted Fyodor After you and Dazai have defended Fyodor, you two were on your way home. You were mad at Dazai because he had cheated on you with Sigma. He said it was nothing serious and that is was just a simple kiss and nothing more, but it was still a big deal for you. You were totally furious at him and he noticed that, he was also really sorry but didn't know how to show you he was sorry

Dazai: Chuuya... I'm sorry... I swear it was nothing I was serious about.