Hiroshi Hoshino moves into a new house and discovers an extraordinary asparagus growing in the yard. After eating it, he transforms into a girl—now going by the name Hiroko. Embracing her new female identity, she starts attending an all-girl high school and befriends a classmate named Rumi. Unexpectedly, Hiroko discovers other boys have similar transformations, including Rumi herself. With supernatural forces threatening Tokyo, Hiroko is tasked with organizing a squad of transformed ex-boys into magical girls to defend the city