Mesu Kyoushi: Injoku no Kyoushitsu  

牝教師 淫辱の教室

Takuyas parents divorced when he was young. His mother remarried Sanada, who had an intelligent son named Eiji. Despite being treated poorly by his brother, Takuya remained at home until one day he couldn't take it anymore and left. He enrolled in high school under his mothers family name. One day, a new teacher arrived at the school - Eiji, Takuyas older brother. While observing them from afar, Takuya noticed that Eiji was having an affair with Miyuki, a popular female teacher. Inspired by this discovery, Takuya hatched a plan to take revenge on his brother and seduce Miyuki in collaboration with Rihoko, the school doctor.