Rui befriends Momo Kashiwabara, who has a reputation for dating numerous boys. They meet Natsuo while shopping, and he saves Momo from being struck by a bicyclist. Momo later asks Rui is she can fall for him. Momo flirts with Natsuo at school but he returns home to take care of Rui, who said she was sick, and Rui reveals that Momo has a crush on him. The next day at lunchtime, Momo kisses Natsuo on the cheek to cheer him up. Later, Momo invites him to her house where they make out in her room...