The sexual act of inserting ones fist into a woman's vagina and the other fist into her anus and then knocking your knuckles against each other through her flesh
-Dude, I was knocking fists on this chick last night...
-Oh man, did you stretch her out good?
-Hells yeah!
-Oh man, did you stretch her out good?
-Hells yeah!
by 47 April 1, 2006