An 11-year-old boy, Takasumi Takane, will be given a new bicycle if his exam results are in the top 100, but his results put him in 112th place. He tells his mother a lie that he placed 92nd, and he tears the answer sheets apart. On his way home from cram school, he accidently breaks the old bicycle that he is supposed to hand down to his little sister, Tamaki. This angers Tamaki. Furthermore, Tamaki accuses him of telling a lie, and he begins to think of her as a nuisance. One night, when he goes to a shrine to look for his missing dog, Chris, he encounters a young man named Yoyogi. Somehow, Yoyogi has the answer sheet marked as “92nd." Yoyogi proposes a trade, but threatens to return the answer sheet to its original owner unless he is given something Takane doesn't need. Takane offers him his sister, Tamaki. At that very moment, Tamaki arrives, searching for Takane and Chris. Yoyogi turns Tamaki into a shining object and swallows her. Takane decides that he was wrong and wants to save her. Yoyogi agrees to restore Tamaki to her original form if Takane wins a race against him, with his broken bicycle. Can Takane win the race rescue Tamaki?