Vagina penis sex in

"When the penis is in the vagina it becomes increasingly engorged," he says, giving his hypothesis of what causes the problem. "The muscles of. The one on top is a female, and she has a penis. The one on the bottom is a male​, and he has the equivalent of a vagina. During sexual bouts that can last for 40 to 70 hours, she penetrates him and uses [ ]. While a vagina expands during arousal, a large penis or sex toy can still cause discomfort when having sex. Penetrative sex (also called sexual intercourse). When something (like a penis or a sex toy) goes inside someone else's mouth, vagina or anus. Vaginal, anal and​.