When a man is preforming anal sex doggy style and just before he blows his nut he hits his partner in the back of the head knocking them unconcious. The sudden head trauma causes his partners rectal muscle to instantly contract firmly around his penis, adding to the sensation of his orgasim. The name is derived from the donkey's unrulely behavior that will make him suddenly kick someone with seeming pleasure along with the idea of him having a huge penis.
That girl last night said she wanted to get nasty but wouldn't shut up about it, so I gave her the donkey blow and got two birds with one stone.
by Simon M. August 10, 2006