Based off my story on AO3: "Vile Hydrangea."
Roles:
Chuuya - Taken by me :)
Dazai,
Akutagawa,
Atsushi.
P.S. Better experienced if you read it first because it takes place after that.
Plot: After Dazai explained why he faked his death, Chuuya quit street fighting and Dazai now owned a flower...