After seeing the ad on f-list for Heart and Fur I was wondering what other Pen and Paper games had sex systems in them.
So far I've come across a few:
Hot Chicks - Inner Darkness has the actual dice rolling mechanics of how it works.
F.A.T.A.L. - The infamous anal circumference.
Big Breasts Small Waist - The BESM sex companion.
A book entitled "RPG Book of Sex" which is copyrighted 1996. (Looks like a D&D supplement.)
That's all I have, I would appreciate if anyone has any they could share, or even their own system they made up. I've seen people that want to play "dice games" on F-List, but usually just them rolling a dice on a table of things they want to happen during your RP and not an actual system.