Aoi used to be a Demon Slayer but since she was so terrified by the Final Selection, she quit and decided to tend to the wounds of Demon Slayers at the BM Although she enjoys being with her friends who she has a sisterly relationship with at the butterfly mansion, she looks down on herself because of her fear. Aoi has blue eyes, black hair put into two pigtails with two blue butterfly hair clippers on each pigtail, she also wears a blue demon slayer uniform and white dress and she is a Tsundere.