Procheilon

The tubercle of the upper lip (also known as the procheilon, labial tubercle, or tuberculum labii superioris) is an anatomical protuberance called a tubercle, located in the center of the human upper lip.

A study published in June 2011 claimed that the greater the prominence of a female's tubercle of the upper lip, the likelier she is to experience vaginal orgasm.

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