I have to admit, it seems a little strange for someone like me to be writing a how to article on writing good sex scenes. Anyone who's read my profile knows that I have the absolute least amount of experience with real world sex possible, none. Yet, if reader response to my stories is any gauge, I seem to know what I'm doing (If I don't, will someone please let me know). So what do I do when I write a sex scene?
The first step in writing a good sex scene is read good sex scenes, and bad ones. Knowing what sucks is just as important as knowing what is great. I have a voracious appetite for erotica. I have been reading it since before it was legal for me to do so. Lots of letters magazines like Penthouse letters and Hustler fantasies. I've collected massive amounts of erotica from the internet ever since it was possible to do so. So I have seen lots of good and bad stories, as well as good and bad sex scenes.
So just what is a good sex scene? For me, a good sex scene is one that draws the reader in and makes them wish, or imagine, that they are there. A really good one makes you wish you were one of the participants. I will admit that different people have different ideas about what great is, but there are some constants in the good ones. The most important constant of good sex scenes is that they don't fixate on just the physical acts.
Sex is something that is felt, deeply and strongly. "My cock thrust into her pussy again and again," is just nowhere as erotic as "My cock felt her clench against it with each thrust into the warm moist folds of her pussy." Brevity is not the goal here, lots of vivid descriptions is. Capture the feelings of the acts that are being described. It's also important to be vivid about the sensations that result. Compare these two descriptions. "My arousal grew as he caressed my pussy, sliding his fingers between the lips." "As he caressed my pussy, sliding his fingers between my lips, my body flushed with heat and sensations, much like electric sparks, rushed from my cunt, causing my body to shudder with pleasure." The second one is vastly better, letting you feel with the character, the sensations that she was feeling.
It also helps if the descriptions are realistic. I need to qualify this, however. Real sex can be incredibly dull, at least if you believe some of what had been written about it. I had the pleasure of reading an interesting book some time ago, "The Hite Report on Female Sexuality." The Hite study solicited women's comments about every possible aspect of sex and compiled them in a book. One of the findings was that at least half of the women in the study reported unsatisfying sex lives. 10% of those having sex regularly had NEVER experienced an orgasm. So realistic descriptions are not about what happens in the real world, per se, but what happens in the real world when the sex is good (unless, of course, your story needs a bad sex scene for plot purposes).