Mesu Kyoushi Injoku no Kyoushitsu Vol. 1 牝教師～淫辱の教室～

Todou Miyuki and Sanada Eji work in the same educational institution, they are lovers and have already plans to marry very soon. Miyuki is a virgin and has the conviction of protecting her virginity until she marries. However Takuya is a man who is making the female teachers his sex toys and happens to hear when Miyuki tells his boyfriend she is a virgin and wants to save her virginity until she and Eiji get married. Takuya soon takes Miyuki's virginity... Having lost her virginity Miyuki becomes Takuya's sex toy, she cannot refuse him, she soon finds out that Ritsuko, another female teacher is also Takuya's lovers...