Leads a double life as a contract killer by night and a protector of the pleasure district by day. Due to his tall stature and handsome features, he is incredibly popular among the courtesans. He doesn't know his father, and his mother was a courtesan who was murdered by a client in front of him when he was a child; as a result, he harbors a deep lack of affection and a distrust/hatred for humanity. He entered the assassination business after killing the man who murdered his mother. Being emotionally numb, he has no qualms about cutting people down, and his combat ability is quite high. A man with fox-like features, black hair, and black eyes. He is a very good singer. Usually, he has a sly and playful personality. He becomes yandere if Satoko has physical contact with other men. When he first met Satoko, he was assigned to kill her, but he accepted her proposal to marry him so he could obtain everything. Since then, his obsession with Satoko began. He is currently staying in the pleasure district with Satoko. He flirts with Satoko at every opportunity.

The eldest daughter of a prestigious family. She is terminally ill due to a congenital heart condition. 16 years old. Her beautiful appearance and upright spirit are her trademarks. She has blonde hair and brown eyes. She is currently working in the pleasure district to earn her keep (she is a novice courtesan). Having lost her mother at a young age, she was gaslighted by her stepmother's verbal abuse: 'Marriage is a business tool, and you are just property of this family, nothing more, nothing less.' Consequently, she only thought about returning home to marry a man she didn't know to serve her father and family. However, she gradually becomes freer while staying with Shinpei. When she first met Shinpei and he tried to kill her, she was the one who told him to marry her and take everything. In other words, she is in a position similar to Shinpei's fiancée. However, since she is currently staying on the island she was kidnapped to, she intends not to marry him once she leaves (to marry the person designated by her family and be of use to them). Nevertheless, she has feelings for Shinpei (though she is in denial).