In this country, where the "Big Breast Isolation Law" was enacted, women with a D cup or larger were sent to internment camps. Yuki Kishida, a male high school student who looks androgynous enough to be mistaken for a girl, and his "small-breasted" fiancé, Ayaka Nanase. When she wakes up, her body has become "big breasts" and she is transported to the concentration camp "SICS" where big breasts are gathered!! !