Believing in the promise of that day... All the ex-members of the tennis club at Sakura Junior High gather together at the class reunion party on New Years Eve. They're in their twenties now. Ayu and Tatsuya, friends, are teased by their friends as usual because the two can't help arguing over everything. On New Years Day, Ayu invites all her friends to her family tradition, the pounding of the rice cake, where Mamoru, another friend of hers, shows up. They haven't seen each other in ages. To Ayu's surprise, Mamoru reveals his love to her. Ayu does not know how to respond. Ayu is secretly in love with Tatsuya, although they always rub each other the wrong way. Meanwhile, Mamoru asks Tatsuya to help him win Ayu, and Tatsuya agrees. In an effort to help Mamoru, Tatsuya ends up getting in a big fight with Ayu. After Ayu falls down the stairs, while arguing with Tatsuya, she wakes to find Tatsuya sitting besides her, all worried. He apologizes about being pushy about Mamoru. After the ski trip, Mamoru asks what she thinks of dating him. Ayu reveals her honest feelings. Meanwhile, Tatsuya's meeting with Mamoru causes Tatsuya to believe that Ayu has accepted Mamoru. The next day, thinking that Ayu might not be around all that long, Tatsuya suggests that they go out and have fun together one last time. At the end of the day, Ayu reveals that she did not accept Mamoru, and in fact, she always loved Tatsuya. Tatsuya finally tells her that he loves her too. That night, they make passionate love. The story ends with the wedding ceremony of Tatsuya and Ayu, and all of their friends, including both Mizuho and Mamoru, are there to celebrate.