Ever since their son grew up and left home, the couple has sex almost every day. They flirt with each other day and night, "anytime, anywhere," but this lively couple is shaken... Their son is coming home for school break. As a parent, it's a happy thing, but Tooru, the father who gets excited every day, can't stand it. His son won't budge from the living room. Wanting to have sex with his beloved wife, Miki, Miki takes her out to a seedy "love hotel."