Smack that ass. Tell to get down on all fours, face down ass up. If you get tired, tell her to use a toy, maybe even one that looks like a ninja weapon? Grab a bite to eat to reinvigorate yourself, but keep in mind the dinner table is not just for meals. Make her dance a little and shake that thong. Some women jiggle more than others. If she is really naughty, get your girlfriend to flash her stuff in public.