A patch of hair on a guy's lower back, just about at the belt line. Speaks of virility to me, and it's extra hot because the guy himself can't easily see it, so he may not be aware of its allure.
Thanks for that link, Merboy. Checking it confirmed my belief that my name was the most popular one the year I was born. In one grade school classroom 5 of us shared it. That sometimes allowed us to stall with "Who, me?" if called upon for an answer we didn't know. ?