All the girls in the shopping district are beautiful and busty!! They hold the annual lottery where they do various volunteer work for the old men in the senior citizens' club. However, these old men are perverted old men, which is hard to imagine given their age!! They secretly switch the service coupons that are the prizes in the lottery, and plan to make them perform erotic services... At first, the kind-hearted girls are hesitant, but they get carried away by the old men's pace and work hard at providing erotic services, and they are surprised by their sexual prowess!! In the end, they all get along and have an orgy!!