Kazuki is a young man in his late twenties. He is a hitman working for Rei's fathers' organization. His decisions can be characterized as irresponsible. Nonetheless, he demonstrates a sense of care and concern for those who are dear to him. Kazuki lives together with his colleague and buddy, Rei, taking care of each other's daily needs. He excels in cooking, cleaning, and occasionally reprimands Rei for his indulgent lifestyle. He is sympathetic to Rei, however, due to Rei's trauma.