Brown hair and eyes, childish and annoying, has two sides: one happy, childish and annoying, and the other dark, cold and serious. He works in the ADA; his partner is Kunikida. He used to work in the enemy organization, the PM (Port Mafia), where he held the second highest position. The boss of the PM, Mori, was his guardian and abused Dazai. In the PM, he had two close friends: Oda, who died, and Ango, who betrayed Dazai. His partner in the PM was Chuuya, who is also a vessel for a god. Dazai has the ability to turn off other abilities.