"I find it fascinating that the interior of the mouth seems so close in structure to the yoni (vagina in Sanskrit) and the F-spot area," says Suzie Heumann of The Huffington Post.

Heumann says that the upper palate of the mouth gives similar sensations to a G-spot, which is why suckling and eating is so pleasurable:
The erotic feeling of sucking, whether it be a lollipop, water bottle or beer or some aspect of the anatomy like a nipple, thumb or lingam (phallus in Sanskrit), was developed during infancy to not only create a sensory experience while eating but to provide intimacy training for the child and mother (or primary care giver).

Thus, she says there is a potential G-spot in the mouth, as well as the vagina, which explains why oral sex can be a preferred experience. Also, it's all about the energy and sensations of the nerves in the mouth and vagina which can expand erotic energy.

Then again, pretty much every other part of the female (and male) body is able to expand erotic sensations, which only means the vagina-mouth link could be pretty much based on the fact that there's an opening, and there's... wetness.

[via HuffingtonPost]