The act of having sex while the guy (on top) wears a very heavy backpack. The guy sweeps back in a long arch and pumps in as deep as agonizingly possible, so that when the backpack slams into his ass he gets a new level of depth. Caution: will break most vaginas
"Dude, I was hittin this one chick with right? Then she said I wasn't gettin it deep enough, so I put on my backpack and gave her a Tennessee VagHammer"
"I feel bad for that one girl, the whole fraternity gave her the Tennessee VagHammer, now she's in a vaginal coma"
12👍 3👎