Masato Kamiya is a supporting character in the Cat's Eye anime series. He operates as a self-proclaimed reporter, but his true identity is a phantom thief known as Mouse, a name he dislikes, preferring instead to call himself a gentleman thief. He leaves a distinctive coin pendant at the scene of his crimes as his calling card. Kamiya presents himself as a cocky, talkative, and slightly egotistical individual with a strong inclination for flirting with women and using his linguistic skills to navigate situations. His motivations are rooted in his own sense of style and thrill for the heist, positioning him as a rival to the Kisugi sisters' criminal endeavors. In the story, he acts as a freelance writer by day, which serves as a cover for his nocturnal activities. His key relationships involve the main characters, particularly the Cat's Eye trio, whom he competes against, and Toshio Utsumi, the detective pursuing the phantom thieves. There is limited information on his character development, as he appears as a supporting figure rather than a central protagonist. His notable abilities include a high degree of skill in theft, a knack for deception, and the use of a coin pendant as a signature item. Physically, he is depicted as an adult male with brown hair and brown eyes.