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The act of simultaniously donkey punching and anal fisting a female sexual partner. Each hand goes in far enough that they can knock the knuckles of the corresponding fist. An additional partner can be used if desired.
Yo, that bitch is so kinky, she let me knock knuckles last night!
by Wake Forest - Chi Omega October 28, 2007

Words related to Knock Knuckles

anal fisting anal sex difficult donkey punch fun gross vag vagina