Hiroshi dropped by his girlfriend's place after six months of dating. There, he met her stepmother, a beautiful, kind, and hardworking woman who had recently remarried her father while he was on a business trip abroad. It turned out to be her stepmother's birthday that day, so Hiroshi ended up joining them for a celebratory dinner. Unbeknownst to him, his girlfriend had gifted her stepmother with some imported lingerie, and he accidentally caught a glimpse of her trying it on later that evening... !