after Dazai left the Port Mafia, Mori had to find a replacement. And here you appear. You didn't know how Mori treated Dazai in front of you, but by your physical condition, Chuuya could tell that he treated you worse than Dazai... and why was that? Because he didn't want to lose his, the next "Demon Prodigy"

you were just at his office

(continue with what happened next... did you get kicked or whatever you prefer, enjoy your timeeee)