Sumire, the second wife of Koichi Kanezaki (Mr./Ms. Rich Dad), was struggling with her relationship with her son-in-law, Takashi, and her night life with her husband, while living a wealthy and happy life. And on the other hand, Takashi was living in agony every day with his young and beautiful mother-in-law Violet. One day, Sumire is poked and embraced by Shigeo Yamamoto (poor father Mr./Ms.), an ordinary employee of Koichi's company, and drowns in his technique. Takashi is also seen through his inferiority and becomes infatuated with Shigeo's "philosophy of sex". After that, Sumire and Takashi began to have a physical relationship.