slam junk

when you or someone close to you has abnormally low hanging balls and you proceed to dribble them against a hard surface and slam dunk them in their navel

inserting ones junk inside while having intercorse

A variation on a handjob, a slam junk is performed by jumping in the air with your arm outstretched, then slamming your hand, masturbation-style, onto the recipient's dick as if dunking a basketball. The more preferable variety of this position is performed with the recipient at a slightly higher elevation of 10 feet, although this is optional.