I heard it said that sex is 99% in one’s head.
I don't know about 99 percent but it is undoubtedly the strongest factor. The idea that we are somehow genetically programed for our sexual desires is ridiculous in a age of strange fetishes that couldn't possibly have a genetic component.
“I heard it said that sex is 99% in ones head.”
....and if such sexual thoughts last longer than 4 hours....