In my story series Canadian Nights, Scott wants to tell Logan a story about something that happened to him a long time ago. "It's not a happy story," he says, "but it's got sex and violence in it - two of your favorite things." Logan laughs at that.
I think for a lot of writers and readers, sex and violence are two favorite things. Some avoid one and relish the other. Some love both. I remember when I started writing slash, or rather, a little bit later, when I told my then 13-year-old son that I was writing X-Men fanfic, he asked me "Do you write action scenes?" I was momentarily unsure of how to answer, although the snarky response, "Yes, but not the kind of action you're thinking about, kid" went through my brain.
I got into slash partly for writing sex. I thought it would be interesting, and a challenge. I've always had writing hobbies but I'd never written anything about sex. I felt that writing m/m sex was a good enactment of "write what you know" since I've been listening to gay men talk about their sex lives for decades. At the same time I thought it would stretch my creativity, since I'd have to imagine what it feels like. Also, since I'm a pretty private person about my own sex life, it appealed to me because it was divorced from my own sexual experience.
My first story series, I Know What You Are, didn't have a lot of plot but it did have a lot of sex. I don't think the sex was gratuitous, even looking back. It was about sex, about how initiation of a fairly dysfunctional sexual relationship affects both characters. However, as I wrote more, I found that I wanted the stories to be about more than sex. Sexual activity is a really good vehicle for a lot of things I want to do with my writing, and it figures largely in most of my stories for that reason. On the other hand, it's not enough to carry a story for very long. Over time, I've given a lot of thought to when to include explicit descriptions of sex and when not to.
To make that determination I generally ask myself: What is the function of the sex scene? If that function is met without the details, I'll just indicate that it happened. But often what I want to do with sex requires the reader seeing them having sex, not just knowing they did. So that's when I write them.
Sex scenes can advance plot, illuminate character and/or relationships, set a mood, set the scene for important dialogue. The last point is particularly true with characters who don't open up so much in ordinary conversation. That's not to say that someone who's a tough guy in most of his life is going to get all hearts-and-flowersy during or after sex, but people do often have less control around sex than around other parts of their lives. Since both of my main characters have a lot of self-control (of very different kinds) I find sex is an opportunity to see a different side of them.
Of course it's not just that you write it but how you write it that counts. The first chapter of the series I'm working on now opens with a sex scene. In my first draft I got it all wrong - it had the exact opposite effect from what I was aiming for. Once a beta pointed it out to me (thank you, kestrelsparhawk), I saw what was wrong with it and rewrote the scene. Now I believe it does do what I meant it to.
Some writers tend to describe in a lot of detail what happens before their characters have sex - lots of kissing, lots of intimations that they're about to have sex - but then fade out and resume the next morning. I do think that that kind of PG fade out can be cheesy, and kind of comic, if it really feels like the author wimped out of an explicit scene that would have fulfilled one of the functions mentioned above better (think the going through a tunnel scene on the train at the end of North by Northwest).
I write almost exclusively in X-Men fandom. It's an action/adventure fandom focusing on a paramilitary group, so combat is an important part of the plot. I wrote explicit sex from the start, but in my early days of writing had the battle scenes happen "off screen."
Combat, in a milieu where it's part of the characters' lives, can have many of the same functions in the story that sex does - it's important to plot, it's an emotionally intense experience, it can illuminate aspects of a character you don't see in more mundane situations. So I think it's worth writing but I did the equivalent of the PG fadeout for a while there, myself. I mostly wrote that way because I know a lot more about sex than violence :-) and was more comfortable writing it. But I worked a lot on developing my skills in writing combat and I think the stories are better for including those scenes.
So... when do you write sex and violence? Do you use the same principles for deciding when to write it explicitly and when to gloss over? Do you think they have anything in common? Please, let me know.