"Now it was said that their particular combination of genders was the perfect match, a complete experience, "the double lock and key," all possible pleasures at once; but Wahram had always found it rather complicated. As with most wombmen, his little vagina was located far enough down in his pubic hair that his own erection blocked access to it; the best way to engage there once he was aroused was for the one with the big vagina to slide down onto the big penis most of the way, then lean out but also back in, in a somewhat acrobatic move for both partners. Then with luck the little join could be made, and the double lock and key accomplished, after which the usual movements would work perfectly well, and some fancier back-and-forths also."