It's mostly a figment of fevered adolescent imagination I'm afraid. Still, if your girlfriend has a good sense of humor, give it a try. Not sure if the rules are any more sophisticated than "lose a piece, lose a piece of clothing", but I think the mate off the board is the real object of the game.
Is Strip Chess A Real Thing?


We tried it a couple of times in our 20's. The fact she barely knows how to move the pieces was a plus. She probably would send me to hell if I propose it nowadays.
So I was looking at other posts from like 4 months ago and someone brought up strip chess. Wtf is it?