"Through frank conversations with cross country mates and cheeky hints in coming-of-age films, I learned that masturbation is something people do to their vaginas with fingers, shower heads and (though I often doubted it) hairbrush handles. I intrinsically knew that what happened when I pressed my thighs together and held my breath was masturbation, too, but as my Encyclopedia of Wank expanded with no reflection of my own methods, it became clear that I was missing a fundamental element of jerking off."