Kekko Kamen (けっこう仮面) is a Japanese manga series written and illustrated by Go Nagai. It was serialized in Monthly Shōnen Jump from September 1974 to February 1978, with the chapters collected into five tankōbon volumes by Shueisha.
It follows the misadventures of a student named Mayumi Takahashi who attends a boarding school called Sparta Academy that is run by sadistic psychopaths. The teachers are constantly looking for ways to torture or humiliate the female students, and from this the teachers derive sexual satisfaction. Takahashi's only protection is from a mysterious nude female superhero—the titular Kekko Kamen. The manga has spawned an original video animation series and numerous live-action films. In North America, the OVAs were released by ADV Films, while several of the films were published by different distributors.
Plot
First-year student Mayumi Takahashi attends a junior high school called Sparta Academy (スパルタ学園), where the penalty for any student (usually girls) making the slightest mistake is being sexually humiliated by the perverted, corrupt and misogynistic teachers running the school, the principal being a demonic, jester-like villain named "Toenail of Satan". However, before the teachers can take their sexual advances too far, Kekko Kamen steps in and delivers a sound beating to the teachers, and usually performs a finishing attack by jumping into the air and landing crotch-first onto her opponent's face.