Hachimitsu Academy, once an all-girls school, has become co-ed, and teen Kiyoshi is one of five boys to enroll. When he is caught peeping, Kiyoshi is sent to the schools prison, where his punishment is carried out.

A second-year high school boy finds himself uneasy during Christmas time due to an experience in the past. However, this year at Christmas, he gets his last chance to ask out a graduating female senior named Haruka Morishima — or one of several other classmates. The story of the anime will be arranged in an omnibus format, with each heroine getting her own version of the story animated. Each heroine will sing her own version of the ending theme song.