The messy result of an extreme anal bashing session, where the insides of the rectal passage divide by zero, falling out all over the other guy's cock.

Variations of this may include the second male inserting his custard cannon into the prolapse, spaffing all over the bleeding mess, re-inserting everything back into the ass canal, and sewing it up again.
Neil's bedroom was a total mess this morning, his gaynal prolapse exploded all over the sheets.
by Source_421 March 19, 2010
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