Hiroshi, who has been dating his girlfriend for half a year, visited her house and met her beautiful, kind and hardworking "stepmother" for the first time. Her father, who was on a business trip overseas, had remarried. Apparently, it was her mother's birthday that day, so Hiroshi, her mother and her mother joined him at the birthday celebration that night. In fact, the present she gave her mother that day was imported women's underwear, and he witnessed her mother trying it on that evening…!