Kako (Fumi Nikaido) is a female high school student. She lives at a restaurant run by her family in Kitashinagawa, Tokyo. Unexpectedly, Kako’s aunt, Mikiko (Kyoko Koizumi), suddenly appears. Kako thought her aunt died 18 years ago. Her whole family is embarrassed by Mikiko’s appearance due to a past incident caused by Mikiko. Kako is also irritated when Mikiko lives in her room. They spend the summer together.

As a child, Ono Tsubasa saw a Shirato baseball game on TV and was amazed at the Trumpet player in the band playing. Now, in order to play the Trumpet, she enters Shirato High School. There, she meets Yamada Daisuke, a catcher for the baseball team. With each others support, they go towards their dream of playing at Koushien.

Ninako Kinoshita has never been in love until an encounter with the school’s most popular boy, Ren Ichinose, leads the two to befriending each other. Ren’s patient and kind personality is a far cry from his unapproachable idol status at school, and soon Ninako falls in love with him. However, she must cope with the fact that he already has a long-time girlfriend.

24 people play a fierce survival game for their own purposes.