Sooner or later, it seems, if you’re writing adult fiction in almost any genre, there will come a point where the story calls for a sex scene of some sort. If you’re writing something having to do with shades of various colors, that point will come quicker and more often. I have faced the dilemma myself with varying degrees of success.
Writing sex is some of the most difficult writing I’ve ever done. Sex is one those issues in Western culture in which there seems to be little middle ground, yet we’re so conflicted emotionally about it, we tie ourselves in intellectual knots. It’s dangerous. The mere mention of genitalia will lose you an entire segment of society. Describe it with vulgar, or street terms and many will walk away from your work without a second thought. Even if it is in character. Yet others will applaud you for your honest characterization.
What some will praise as “torrid” or “erotic,” others will condemn as “pornographic” and “obscene.” So tread carefully. Know your genre and know your audience. Certain genres simply will not tolerate graphic sex in any form. Some even frown on the mention of certain anatomical parts.
When you do decide that depiction of a sex act is appropriate for your story, you have to get down to the mechanics of writing a memorable scene. And that is difficult.
In my opinion, the biggest pitfall most writers face is the temptation to spend their time and energy on rendering the mechanics of the physical act. After all, it is a physical act, isn’t it? The problem with this is pretty much everyone over the age of twelve is familiar with how the process works. Showing the reader how it works again on the page of your short story or novel will risk appearing either monotonous or sophomoric. Neither of which (I assume) is the effect we’re shooting for.
The solution to this problem? A bicycle ride.
Yep. A bicycle ride.
Consider, if you will, your main character rides her bicycle the ten blocks from her home to work every day (she’s environmentally conscientious, or maybe just poor). Do you describe the mechanics of riding the bike? Do you show her pressing down on each pedal with her feet and legs to propel herself? Do you describe how she minutely adjusts her body weight to maintain balance? How she steers? Brakes? Shifts gears? Probably not. Your audience already knows how to operate a bicycle. Telling them again is wasting their time.
Unless something unusual were to happen (like having to dodge a car) your depiction of the bike ride would only have the barest details of the bicycle’s operation, just enough to occasionally remind the reader that your character is riding a bike. Instead, your scene would consist largely of how the character feels (is it sunny and warm, a pleasant ride, or cold and windy?), what she’s thinking about, what she sees and hears along her journey, how her body responds to the exercise.
Now if she takes the ride with her romantic partner, you would describe their relative positions as they ride, but still concentrate on the sights, feelings and desires of your character. Much of them would now just be related to her companion.
The same rules apply to writing sex. Concentrate less on the mechanics (unless something unusual happens like, say, falling out of bed) and more on the emotions involved. That will go a long way toward making it a successful scene. There’s an unwritten rule in horror fiction that says “do not describe the monster. The reader will imagine worse than you could possibly describe.” I’d posit the opposite for sex scenes. We, as writers cannot describe anything as beautiful and erotic as our readers can imagine, so maybe we shouldn’t do more than point them in the right direction. After all, the most important sexual organ in the human being is the imagination. Use that to make your scenes work for everyone.