Hibiki and Naoya are parents-in-law. Hibiki was trying to be a good mother, but Naoya is a man around the age. There is no reason not to be aware of the young and beautiful Hibiki as a woman. The barren days of patience debilitated Naoya. Naoya who felt the limit decided to leave the house. Finally, the three parents and children went on a hot spring trip, and this should have cut off their feelings for Hibiki ...