Atsushi lacks confidence in himself due to his past, particularly being thrown out of his orphanage and being called worthless. However, this gave him an iron-clad determination to survive in life, and not die. Atsushi is sarcastic and sassy, yet kind and pure-hearted and wants to do his best to help and protect others. He has a selfless nature, putting others before himself. He trusts his mentor Dazai with his life. He uses they/he pronouns and is a trans man.