Call Me Tonight

A high school girl working by night as a hotline owner, Rumi "Suuko" Natsumi, receives the call for help of a young man, Ryo Sugiura, who claims to transform into a destructive monster every time he masturbates. Amused and attracted by Ryo, a shy yet good-looking pulp horror aficionado, Rumi seduces him during their date on a diner, which proves him right when he transforms right there. Rumi runs away with him and, upon observing that he turns into a monster whenever sexually aroused, yet is capable to contain it by force of will, decides to try to cure him by habituating him to sexuality. They continue their date into the city's red light district following this plan.