Dazai is a young man who works for the Armed Detective Agency (ADA) as a detective. He is an ability user with the ability to nullify all other abilities. Dazai has a fascination with and a deep loneliness that can’t be filled so he acts silly and unserious to mask it. He cares for his co-workers and took what Oda said about making the world a more beautiful place by helping people to heart.