Actually, I have thought of one folk song that I think is genuinely sexy. I can't remember it's name but it's on one of Ramskyte's tapes (yes tapes).

Young carter lad driving horse and cart, gives young woman a lift, and they let horse set the pace, and gradually the draw of the horse and the motion of the cart combine to a more personal rhythm...

Chorus goes

"And it's ride on Dobbin
Well done Dobbin
Gee up and way-oh"