Bungo Stray Dogs Vol. 8 (manga)

Atsushi's far-fetched idea to form an alliance with the Mafia results in a summit between crime boss Ougai Mori and Armed Detective president Yukichi Fukuzawa. But when negotiations fail, Dazai has no choice but to infiltrate enemy territory alone to secure Q. There, Dazai runs into some unexpected trouble...until a familiar man appears before him...!