A busy mother asks a "rental mom" to take care of her son and the housework. When the beautiful rental mom Yui arrives, her son is excited! Yui will do anything he asks her to do, from cleaning to cooking to laundry, and even teaches him how to Yui. However, when he sees Yui's breasts, he gets an erection. Then Yui gives him a blowjob! And his obedient Yui's erotic requests escalate...