Monami, a serious college girl, and her boyfriend both found themselves struggling with sex as they were each other's firsts, leading to Monami's dissatisfaction. One day, Mr. Takeshita, a long-time friend of her father, visited their home and, amidst the influence of alcohol, they ended up having sex. Monami was utterly captivated by the experienced middle-aged man's caresses, and from that day forward, she found it easier to reach orgasm with older men. Her insatiable sexual desire led her to the point where she even began seducing them on her own.