Mari (マリ Mari) was a girl living with Keisuke Jin, whom she calls grandfather (おじいさん ojisan), on a hospital near the ocean. According to Keisuke, she was waiting for her father, who is missing for some reason. She was protected by Takumi Inui (Kamen Rider Faiz) and his Auto Vajin when they were attacked by the forces of the revived Badan Empire, before Jin transforms into X-Rider and attacks him. In aftermath of the film, she was seen assisting Jin on treating his patients.