... Of Days Gone by is the 11th chapter of Bungo Stray Dogs.
Chuya fights Dazai, who isn't trying to fight back. Dazai reveals that getting captured is part of his plan to find out who put the bounty on Atsushi, and to spite Chuya. He blackmails Chuya into letting him go by threatening to reveal all of the Mafia's secrets to the authorities if he kills him. On the cargo ship, Atsushi encounters Kyouka and Akutagawa, who attacks him with surprising animosity. Kyouka points a gun at him, but he disarms her and mocks her for thinking that she can leave the Mafia. Just as Akutagawa is about to kill Atsushi, Kunikida shows up on the Agency's boat, yelling at him to jump. Kyouka reveals that she has planted dynamite on the ship, intending to sink along with it. Atsushi hesitates because of his desire to save Kyouka when Kunikida yells at him to jump and that he can't save everyone, but Atsushi, deciding not to give up on her, runs back into the burning hold to save her, and faces off against Akutagawa.