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.

A high school teacher and swimming club advisor, Aoki, receives a fierce attack from his former student Yukishi, who had to quit due to an injury. They gradually become physically involved. Aoki has a fiancée named Kagawa, but he can't end the relationship with Yukishi. Every time Yukishi ejaculates inside her, she is overwhelmed by unknown pleasure, and her well-trained beautiful body slowly drifts away from her fiancé…