STARS-529 The swimming club advisor teacher Aomiki Momo can't bring herself to marry her fiancée (colleague) because she enjoys it too much when a student who deliberately repeats a grade comes inside her.

Aoki, a high school teacher and adviser to the swimming club, is attacked by his student, Yuki, who quit playing due to an injury, and gradually begins to forgive his body. Aoki has a fiancée named Kagawa, who is his colleague, but he cannot dissolve her relationship with Yuki. Every time Yuki's semen was spit out inside her, her unknown pleasure attacked her, and her well-trained beautiful body gradually drifted away from her fiancée...