Long ago, Fujishiro Kosuke declared his love to his childhood friend, Sayaka-chan. But his pledge to save his first sexual experience for her takes a shocking turn when he's suddenly abducted and thrown into a secret prison run by beautiful women in fetish gear. His seductive kidnappers will use every kink at their disposal to try to rob Kosuke of his virginity. Who are these women, and why are they trying to break Kosuke's solemn promise to Sayaka-chan?