The sign for this is clamping your hands, opening and closing 3 times like a crab and saying "clammy fanny" in a voice like 'Lenny's' from the the story 'Of Mice and Men'.
One who has dominated the asshole of his or her partner. One whos skills rival that of a bum ninja.
Wow hunny, you are my fannychampion. No one has ever hit my asshole's gspot as quick, or as hard as you. You are, my fannychampion. Now lemme suck my shit off of your dickjust because you did so wonderfully.