If I might quote NS, an authority on hosiery
It disturbed the shit out of me when I thought about it. I was a smart boy. Smart boys are supposed to be rational. So, when I was in college I figured out a rationalization for this. There wasn't that many women who wore sheer black stockings in college, but sometimes I would go into the city and see the well-dressed office workers walking down the street on their lunch breaks and make scientific observations of their legs. I noticed that where the stocking stretched itself thin to go over a wide part of the leg, such as the muscle of the calf, it became paler. just as a colored balloon becomes paler when it is inflated. Conversely, it was darker in narrow regions such as the ankle. This made the calf look more shapely and the ankle look more slender. The legs, as a whole,looked healthier, implying that just above the place where they joined together, a higher class of DNA was to be found.
Q.E.D. My thing about black stockings was a highly rational adaptation. It merely proved how smart I was, how rational even the most irrational parts of my brain were. Sex held no power over me. It was nothing to fear.