Hyoi and Ryoi, a pair of benevolent warriors disguised as cats, must face the evil Jukokubo, who has unleashed an unholy, tentacled terror on the students at their school. Charged with defending their classmates and the rest of the world from this bloodthirsty force and its monsters, Hyoi enters the school in human form while Ryoi stays disguised as a cat so that they may quietly track down Jukokubo before he can attack any of the other students.