[Gay]

Penis captivus

 It's an important knowledge to share here.

 Penis captivus describes an event that occurs in rare instances during heterosexual intercourse when the muscles in the vagina clamp down on the penis much more firmly than usual (a form of vaginismus), making it impossible for the penis to withdraw from the vagina. There is only one known report of penis captivus, in a letter to the British Medical Journal relating to an apparent case in 1947. According to the BMJ, this condition was otherwise unknown in the twentieth century.
 Penis captivus should not be confused with the relatively common condition vaginismus, though it probably only occurs in situations where the female partner is subject to this condition.
 he first report of the phenomenon, in an 1884 article by the fictitious Egerton Yorrick Davis in The Philadelphia Medical News, was later discovered to be a hoax perpetrated by Sir William Osler.
 Historians speculate that he was annoyed by an editorial published in the same journal by Dr. Theophilus Parvin, "An Uncommon Form of Vaginismus". Both men served on that respected journal's editorial board.
The hoax and the rarity of occurrence have created a situation in which many medical professionals believe the condition is non-existent.

 http://en.wikipedia.org/wiki/Penis_captivus