The theme of sexual humor in a school setting is not new. One of the earliest and most influential examples is the manga Harenchi Gakuen (Shameless School), created by legendary artist Go Nagai. Serialized in Weekly Shōnen Jump from 1968 to 1972, the manga was groundbreaking for its era, featuring racy humor and sexual innuendo that sparked significant controversy. The series received heavy criticism from Parent-Teacher Associations but went on to influence future generations of manga artists, including Osamu Tezuka, Rumiko Takahashi, and Hideo Azuma. Harenchi Gakuen was adapted into a live-action TV drama, a film, and an OVA.