So I was doing sex with this girl. Then I tell her to get on her stomach to put it from behind and I smell some heavy odor. Is that her vagina smelling or asshole? It wasn't smelling like fish which I thought is what people say vagina smells like. It smell more musty and dirt like and kind of body odor like sweat all mixed together and made me lose erection.

Is that kind of smell normal of you do from behind?