Err... I don't know where you got that impression, but it is hardly accurate. Fantasy traditionally has had that as one small branch, but it certainly hasn't been true of the whole, or even the majority, even with "epic" fantasy fiction.
Okay, well "Fantasy" is a pretty broad term. If you search Fantasy on amazon you can get them comic book Bone, Charlette Harris, a lot of Vampire books...yadayadayda. I suppose I was refering to the traditional "Epic" Fantasy that Tolkein made famous. I, personally, am not a fan of books with descriptive sex scenes but I would never not read a Martin book because they involve sex, or involve it in a review. Typically this style of fantasty is always good vs. evil, the old God vs Satan with different names. It doesnt seem to be as common a theme as it was in the eighties and early nineties.
Again, I'd object to the use of the word "traditional" here, even though it does have some accuracy, as Tolkien's work certainly utilized many traditional sources. But even as far as "epic" fantasy is concerned, there were several who preceded Tolkien, including E. R. Eddison, William Morris, etc. I do agree that many who followed Tolkien's lead also had some of the characteristics you mentioned in your earlier post, but as I noted in my response, even in epic fantasy of a more traditional sort, this was by no means the main sort of tale told until after the growth of Tolkien's popularity.
However, specific details aside, the point that many readers of imaginative fiction (and this includes both fantasy and sf) object to violence or (especially) sex in their reading has long been noted. Colin Greenland devotes a chapter to this reaction toward the New Wave's reaction against the rather Victorian approach of much sff up to that point in his book The Entropy Exhibition. It is, appropriately, titled "Love Among the Mannequins", and it examines the entire issue rather well.
My own take is that my only objection to such material is when it is gratuitous; when it serves no genuine narrative purpose but is simply there to titillate in a rather adolescent way. On the other hand, when it does serve such a purpose, either as genuinely useful insight into character, to develop a point in the plot, or as metaphor (as in Moorcock's
The Brothel in Rosenstrasse or Nicholson Baker's
Vox, for example, where it serves on all three levels), then I have no objection to it, no matter how explicit it may be. The first is simply bad writing, the second may be using what some still consider to be controversial material or approaches to address a point, but is nonetheless good writing....
As for finding out the title of the novel mentioned in the opening post... as that was Joseph's most recent post, and it took place about 6 months ago, I rather doubt we're going to have an answer to that one anytime soon....