Yoshimura Mamoru was accepted into a school for Beatrices due to his high intellect. "Beatrice" are people who have special abilities. On his first day, he meets Ayako Takasu, aka the Beatrice's Angel of Death, a pretty and popular female student who has exceptional Beatrice abilities. During their first encounter, Ayako, who's usually a cold person and is regarded as somewhat of a loner, suddenly confesses her feelings for Mamoru. After Mamoru becomes inducted into the Student Council as Ayako's aid, he becomes involved in the dangers and mysteries of the Beatrices.