Shun'ichi Minami possesses good looks and does well academically in high school. Chiyomi Horikiri is a bright girl who likes dancing. They were childhood friends and also their first loves, but after Shun'ichi Minami's father disappeared they hardly talk. On a storming night, Chiyomi Horikiri has an argument with her parents over her future course and leaves home. While trying to avoid the rain, Chiyomi Horikiri wishes that she go back to her childhood. Suddenly, Chiyomi becomes 15 cm tall. Shun'ichi Minami happens to see tiny Chiyomi Horikiri. She tells him that she doesn't want anyone else to see her, and Shun'ichi Minami takes her his home.
At a high school entrance ceremony, high school student Kotoko Aihara, who isn't that smart, notices pretty boy Naoki Irie. She falls in love with him immediately. Kotoko initially doesn't express her feelings to him, but finally has a chance to tell him how she feels. Unfortunately, Naoki turns Kotoko down, saying "I don't like dumb women." One day, Kotoko Aihara's house is severely damaged by an earthquake. Until the house is rebuilt, Kotoko Aihara and her father decide to live with her father's friend. When Kotoko Aihara moves to her new temporary house, she is surprised to learn that Naoki Irie lives there as well.
