Рио

Rio is Mao's twin brother. He doesn't have other interests aside from reading books, and thinks he is very plain. His right eye is blue, same as Mao's left eye. One day, Rio is hit by a car while trying to get a cat off the road and a mysterious figure asks him whether he wants to live or die. Choosing to live, Rio wakes up in a strange new world, in the body of a cat! After escaping from an angry mob, Rio is saved by the magician Tarnist and enters a contract with him, agreeing to become his cat familiar despite Tarnist calling him "the weakest of cats". Rio and Mao are the reincarnation of Hilario, "the immortal and most powerful cat" and Tarnist's previous cat familiar. After reuniting with Mao, Rio finds out that he got the "body" of Hilario while Mao got the "memories".