SPRD-928 - My son is way bigger than my husband: Temptation at home

The Sakamoto family seems ordinary, but Mizuki is deeply unsatisfied with her husband's performance. Everything changes when she notices her son's massive bulge, which dwarfs her husband's. When her son asks for advice on his first sexual encounter with his girlfriend, Mizuki seizes the opportunity to take matters into her own hands, offering to teach him herself.