Dazai is a young man with mildly wavy, short, dark brown hair and narrow dark brown eyes. He 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. Regardless whether he is on the side of killing people or saving them.