Now an official member of the Agency after passing their entrance exam, Atsushi is assigned to his first case right away with Tanizaki and Naomi. Though deceptively simple on the surface, there's more than meets the eye...

Though saved from the Port Mafia by Dazai's intervention, Atsushi feels responsible for bringing trouble to the Agency's door. Rather than risk another attack because of him, Atsushi decides to leave the Agency and makes a call to the Port Mafia...