Seiran Island, the land of paradise, aka the land of filthy debauchery, where any sexual acts are permitted and enforced by the Pervert Law. Junnosuke, a transfer, is a virgin with pride who despises sex with no love. However, sex is a duty of the island residents! Virginity is a serious crime!! All those who refuse sex will get guillotined by the Future Seiran Homeland Organization (or FS)!!! Junnosuke decides to protect his virginity with his dear life, evading all perverts along with his young virgin sister, Asane. However, they run into Nanase Katagiri, the school's legendary virgin hunter #$%!*...!