by Richard mor October 19, 2015
When a man bends over and masterbates fastly while someone else fingers him with 2 fingers from behind and rubs his testicles.
Sarah: "I'm so embarrassed! I walked in on my parents doing the finger jack."
Mark: "That really sucks.."
Mark: "That really sucks.."
by poopyodj June 21, 2010
by Paul July 18, 2003
The act of finger penetration to either the vagina or anus, while from behind. This can be accomplished standing, sitting, bent-over, or preferably while she's asleep with her back to you.
While my girl is blowing me in my lap, I like to finger jack from the back to pass the time. Then I cram my fingers up both of her nostrils so that she can smell her dirty ass all day long.
by Finger Maniac March 03, 2011