The Best Sex I Ever Read: Mrs. Caliban

My personal rule is that it has to be doing something besides the literal sex — revealing something that could only be revealed through that sexual dimension, and the introduction of that erotic dimension, into a world. If you have a character walking down a sidewalk, that scene needs to be doing something more than the literal passage down the sidewalk. Even if presumably the literal passage down the sidewalk is quite important, it needs to be revealing the conventions of the character, the world, via that physical transaction.
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