It is not Tag. It is not Battle Royale. It is Battle Royale Tag. Sena walks up to the school rooftop to return Yudachi's handkerchief. Yudachi is not there and Sena falls asleep waiting. It is dark, she is confined and locked up at her school when Sena wakes up. The school has turned bloody red and the girls have to fight to the death. Who will survive the carnage is up to the girls.

Chronicle of the After-School Wars

One summer day in her second year of high school, Aki sees her school's boys' baseball team playing in the Koshien (the National High School Baseball Championship), and unable to stand still, she sets her mind to start her own club. One day, Samejima, who used to play for the Japan University of Physical Education's women's softball team, comes to the school as a physical education teacher, and Aki goes to ask her to become the coach of the baseball team...