I stumbled across a rather interesting essay on erotica and aesthetics while surfing the web, and I wanted to reproduce a couple of brief passages here, since they are well-written, and happen to align with my own position on sexual expression and fantasy. The title of the essay is "The Erotic as an Aesthetic Category", and you can read it in full here. The website also has a number of other interesting philosophical essays on a variety of topics, so if you've got a large block of time to kill, you might like to check it out.
"Erotic literature is thus bound to explore every possibility, even those possibilities that someone might regard as appalling, morally, socially, or psychologically, but that curiously contain the power to arouse. If this reveals something about the unconscious and about the natural terms of the erotic response, it would be wise to be aware of it and deal with it. Or, as Jung might say, the unconscious can become too energized with it, and acting out an irrational response becomes more possible.
"Whether or not this is a real danger, it still behooves human curiosity to see what is going on and represent truths, however disturbing. The erotic as an aesthetic category does mean that, like other aesthetic categories, the requirements of morality, although independent, are not otherwise suspended. Art, literature, and fantasy are one thing, action is another. Some people confuse them, both that fantasy spills over into action, and that the limitations of action are thought to require the suppression of fantasy." (my italics)
"The truth is that Greeks and Romans found human bodies and sexual intercourse beautiful, interesting, and wonderful -- and funny. And if its representation effects an erotic response, so much the better -- a divine gift. This may not be agreeable to religions that mandate tightly circumscribed sexual expression, but, for better or worse, modern life has broken through such restrictions. Promiscuity and disease are not good effects of this, but then one discovers that the Greeks and Romans thought no better of promiscuity than we might. Their sexual explicitness did not imply sexual license, an accommodation and a balance that has not yet been struck anew in popular or elite culture. Mere disapproval or alarm at erotic representations will not do this job. An anhedonic moralism that would suppress them instead would contribute nothing to the richness of human life." (my italics)