The protagonist Kiyotaka Ayanokōji is a student of D-class, which is where the school dumps its «inferior» students in order to ridicule them. For a certain reason, Kiyotaka was careless on his entrance examination, and was put in D-class. After meeting Suzune Horikita and Kikyō Kushida, two other students in his class, Kiyotaka’s situation begins to change.