A father and son who have taken a liking to the busty housewife next door, Haruka, apply to appear on the popular TV show, "Welcome Mom!", hoping to invite her to live in their home. When the staff visit Haruka's house and explain the purpose of the project, she seems confused. However, she is persuaded by the staff and her husband, and ends up living in the Ozawa family as a surrogate mother. As they live together, the true nature of the perverted father and son becomes clear. A turbulent development awaits, including breastfeeding sexual harassment play from the child, bathing together with mother and son, rape by the father, and a threesome with father and son.