Work Text:
Chuuya has two types of anger. The first one is cold, serious. The people who cause it are likely to be crushed.
The second one is rarer. It burns hot and loud, expressed in shouts and annoyance. It's more immature. (It's also more fun.)
Not much will cause it. In fact, it usually only concerns one person.
Chuuya is aware of this. He doesn't need anyone to point out that he's acting differently when he's pissed off because of Dazai.
He's also aware that Dazai is similar in that respect. He's annoying with Chuuya, pushing his buttons, taking stabs at Chuuya's choices and appearances. He's not pleasant like he is with Oda and Ango. But he's also not as cruel as he is with others, notably Akutagawa.
Chuuya keeps his observations to himself. They work well as partners, no matter how much they complain about each other.
And to be honest, he kind of enjoys bickering with Dazai. It's a complete change of pace, being allowed to be immature, to blow up at someone.
He suspects that it's similar for Dazai. Perhaps even more for him than for Chuuya.
So, they continue like they always have. Fighting, yelling, bickering, and when it comes to it, they have each others' backs, trusting one another.
They're partners after all.