The local inn's landlady demands rent to be paid at the beginning of the month, forcing Hibiki Amawa to find his job as a P.E. Teacher as soon as possible. When he checks into the nearby school, he discovers that the man-hating Principal only hires female teachers. Discourged, Hibiki returns to the inn only to find that the landlady plans on Hibiki getting the Job. She dresses him up as a woman, and Hibiki returns to the school. The Principal says that a test is required of ""her"" and that is to help a young student named Fuko run the 50 meter dash without tripping. After futile attempts, Hibiki whispers to Fuko, who, once returning to the starting line, hitches up her incredibly long gym skirt. She then runs the 50 meters, and jumps into Hibiki's arms. Hibiki gets the job as the PE Teacher, and Fuko begins to expirience some puzzling emotions about her ""female"" gym teacher.
Physical Examination Day has come to Fuko's School. The Boys plan on upholding the tradition of pinning up results of the examination on the bulliten board, including ""bust size"" and ""nicest body."" However, Teacher's take extra caution this year, and plan to have the Examination in a windowless soundproof room. Will that stop the boys from getting the dish? Meanwhile, Fuko has become embarassed about her own bust-size and becomes rather preoccupied comparing hers to other girls'. Suddenly, the Vice Princepal has suspicions about Hibiki, and declares that ""she"" must partake in the examination as well. Is the Cat out of the Bag?
Reiko Mukogawa exposes Hibiki's identity with photographs from her visit to the hospital. With this evidence she calls upon the parents and students of the school to promote its change to an all-girls institution. Fuko Kuzuha takes a stand against this and rushes after Hibiki who is shamefully departing from the city.