Um, this isn't THE answer, but i saw the Luniz in Portland in 1998, and Numskull had a hilarious song called 'x-Games', the hook went:
'X-Games!!! Butt-naked sex games! Fuck the Beer, Fuck the Weed, its the NEXT Thang!!!'
Shit was super funny.
But, for real, I bet it was some backpack underground rappers who were on the college circuit playing at (white) private colleges in around 1990 who got hooked up with some and fondly reminiced about it on wax....