Ichinose-kun wa Koufun Dekinai

Aizawa, a womanizer and sex lover, has a serious dog-cat relationship with Ichinose. One day, Aizawa meets a girl he likes at school and takes her to the infirmary to play around. However, when he tries to undress her, the girl transforms into Ichinose! What is Ichinose’s body’s secret?

(Source: Shueisha, translated)