An interesting sexological quirk: a dorsal curvature (curved outward) causes pain in the "doggy style" position. A man with such an "instrument" shared his findings, and I had to confirm he wasn't exaggerating...
We're talking about a "watering can" bend—the tool of carnal pleasure seems to be in a "bridge backward" pose, forming a letter "C" with the tip pointing away from the belly. While most "swords of love" are straight, when they are curved like this...
In short, on the knees—it's no good. Missionary—the same story. Apparently, this rebellious glans scrapes against the bladder, and pleasure is out of the question. The only thing left is the side position! It's likely that owners of such non-standard organs invented the Kama Sutra—a rational person won't hurt their partner (unless it's BDSM) and will try to adapt their features for mutual bliss.
PhD psychologist Nelli Verkhovska explains why dorsal curvature causes discomfort and how to adapt sexual positions for mutual pleasure.
Author’s self-portrait, 21.06.2015
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