The "Dirty Quincy" is the act of, during intercourse, the lady's pet dog (usually a pug) sneaks onto the bed, crawls between the four splayed legs of the humans, and licks the starfish on the male member. This is usually accomplished in the missionary position, but has been know to occur in many other positions as well.
I felt on the verge of an explosive climax, when POW! I got "Dirty Quincy'd" by an all-black pug! Instant flaccidity!