I guess it all depends on appropriateness to the actual book. In tales like the Mabinogion there's plenty of him lying with her and her lying with him after being overcome with lust, and the frankness and everydayness of the fact is something perhaps greatly to be desired! Tolkien say was just of his time - in the 19th century they didn't translate Aristophenes because he was too dirty (and he is) and they took all the filthy bits out of Shakespeare, and that continued well into the late half of the 20th century. So Aragorn and Arwen are somewhat sexless, and mightily idealised, but that's quite appropriate for that book. At the other extreme I've flicked through a few fantasy books which start with pornography and go on (probably the ones mentioned here, I never got as far as noting the author) and just find them a total turn off, and misogynist to boot. Sex scenes are the hardest things to pull off, if you'll forgive the metaphor, and they only work for me when there's a character and interaction that works -
but eroticism, ah, that's something else. I think there's plenty in fantasy. The withheld and imagined.
Alison