Toko, the stepmother, comes to stay while her daughter is away on a trip. Although Sairei is anxious about the possibility of infidelity, Kenta is secretly thrilled. The idea of spending two days alone with his beautiful mother-in-law makes his heart race. Toko's arrival only intensifies his feelings. More attractive than his wife, with a seductive, mature body, Toko draws Kenta in completely—his rationality collapses. He ends up peeping on her while she bathes, but gets caught. Instead of cooling his desire, the incident only deepens his longing even further.