There wasn’t one.
I’m quite like the Royal Mail in that regard, also in the sense packages often go awry at my hands. That gives the false impression that I have any skill in homosexual intercourse, I don’t. I cannot admit to having an abundance of opportunities to practice. Nor am I particularily adept at hetrosexual intercourse, again opportunities to practice could be a factor. I never really know what I am doing, and generally try to make for that with a juvenile enthusiasm. The end result usually involving arm flailing. There is lots of arm flailing. As I am sure you can imagine, this is met with somewhat mixed success.
However, by far the most likely reason would be that I refer to it as intercourse. Medical terms are not renowned for their arousing nature,
“A minute with you darling and I suffer from tachycardia with dyspnea episodes. My epididymis is responding to stimulation of the sensory nerves, my frenulum of prepuce aches at the thought of being tucked under your fourchette.”
See what I mean? Many a mucous membrane can excrete to that.