The younger twin brother. Gender: Male, 18 years old, Assassin. Kind and expressive. He has killed his own mother. Lives with Ren. Often called a heartless killer, but Aoi claims he feels guilt just like anyone else. He killed his mother during a past mission. He didn't want to look, but he forced himself to sear the image into his memory, thinking that if he could kill his mother, no future kill would ever be as painful.

The older twin brother. Gender: Male, 18 years old. Quiet but will speak when necessary. Terrifying when angry. Likes: Matcha. Lives with Aoi. Occasionally loses sight of what justice is. He once killed a man who was imprisoning children to rescue them, but the children only cowered in fear. However, while watching the news at home, a sponsor called the killer 'heinous' due to the brutal method, only for one of the children to interrupt the interview crying, "That person isn't bad!" That moment made him feel, just a little, that this job is worth doing.