Osamu Dazai was the youngest executive with the Port Mafia, the most notorious underground crime syndicate in all of Yokohama. Dazai is a mysterious person, his true intentions are never revealed unless he reveals them. The person who got closest to the truth of his personality, as acknowledged by Dazai himself, was his friend Sakunosuke Oda, who recognized that Dazai shall linger in the darkness forever, as there was nearly nothing that can surpass his mind.