Tutor Kitayama falls in love with his adult student Ichika, and their relationship is going well despite the uneasy distance between him and her disapproving mother, Yumi. One day Yumi declares that she must keep “bad influences” like him away from her daughter and suddenly starts tormenting his cock. Too stunned to resist, he is forced into one unwanted ejaculation after another. Once that boundary is crossed, Yumi repeatedly drains him through sex until his resistance finally gives way and he becomes hopelessly hooked on what she does to him.