Or in laymans terms, when one sucks a cock at the same time they are also beaming Schatner off the Enterprise....the sucker is the crapper.
Note: The money shot should occur at the precise moment of final fecal release, thus synchronizing anal closure with ejaculation.
In the 16 hour traffic jam before the Phish show, we observed a woman run into the woods with her boyfriend. The two perched on the steep banking, not hardly out of sight of the headlights, when she pulled down her dress, revealed her stark white ass, and assumed the squatting position. She was squatting too long to merely urinate and was obviously laying serious cable. To our amazement, her head dissappeared into the mans crotch!! Social morays be damned, this was a reverse blumpkin, and the symphony of car horns signalled the glee and elation of the stunned masses.
The odds of successfully navigating an asteroid field are about the same as receiving a reverse blumpkin!
The Actual meaning of a Reverse Blumpkin is when the female sits on the toilet and poops while the male is on his hands and knees eating out her pussy.
Boyfriend: You want me to give you a Reverse Blumpkin?
A member of the Blumpkin family, the Reverse Blumpkin occurs when a woman performs analingus on her partner while he urinates, thus simultaneously stimulating both anus and urethra in a two-headed monster of erogenous pleasure. This fetish works especially well for those unable to achieve the erection-while-pooping necessary for the classic Blumpkin.
from the book: Dirty Sanchez's Guide to Buck Nasty Sex