I always loved that book "Everybody Poops." It's true and it's leveling--you're not gross because you poop, and no one is so much better than you that they don't poop.
I think there should be a corollary book for slightly older children called "Everybody Fucks." (I guess some people don't, although not many if you count masturbation. Still. A lot of people fuck.) Same leveling effect. Same much-needed perspective: that fucking doesn't make you bad and it doesn't make you special. If you're reading this, I know you know, but as a teenager I could've used that message: that fucking isn't a privilege or a mystery or a shame. It's just part of being a biological critter.
And as with pooping, the goal isn't not to do it, but to do it right so you don't make a mess. You'll do better learning to use the potty than trying to never poop.
(In this analogy, the potty is a condom.)