We fell in love, got married, and after 5 years of being a married couple, our relationship hit a rut and we became sexless. Jun, her simple and serious husband, is rejected by his wife and spends his days in agony, unable to attend to her entertainment. One day, my girlfriend's wife had to come home for three days for a friend's wedding. Worried about the housework while her wife is away, her wife's older sister Saki comes over with side dishes for her. ``Even though you are young, you guys are already sexless...Oh, so am I...'' The frustrated married sister-in-law seduces the young Jun, who has a lot of sexual desire. And while her wife (sister) was away, the two devoured each other's bodies... ``We're in-laws, but we're siblings, so it's not cheating.'' Jun ejaculates over and over again due to the ripe body and trembling pleasure that he can't experience with his wife.