Let's talk sex scenes:
First off, I'm not the biggest fan of them. Seriously, I'm not. Most sex scenes are superfluous, add nothing to the story, and bore the ever-loving hell out of me. A majority of sex scenes land in the book with a thud, out of nowhere, and bring everything to a screeching halt. I almost feel like the writer reaches a point where they're writing by the numbers and then reach a note that reads <insert sex scene here>.
That being said, a well-done sex scene is one of my favorite things. I've read some that utterly terrified me (and gave me nightmares), some that made me cry, some that made me cheer, and a few that made me go find my husband with an evil gleam in my eye.
This brings me to my philosophy on sex scenes in MY books. It has to fit the story, it has to progress the characters in some way (their development as a person, their relationship, etc), it has to advance the story, and the level of explicitness must fit the rest of the story.
The PRETTY WHEN SHE DIES trilogy has sex scenes in it because it fits everything about the story, the character, and the world. Amaliya is a woman who is very comfortable with her sexuality and sex. She doesn't give a damn about societal rules about sex. The vampires in the series use sex for feeding, control, and power (rarely for love). In fact, attaching love to sex is unusual for the vampires in that universe. It was fun exploring the difference between how humans and vampires regard relationships, sex, love, and fidelity.
Yet, other books I've written don't need sex scenes at all, or only need the sexual relationship of the characters vaguely commented upon.
I grew up in a very repressed culture. Sex was bad. It wasn't spoken about, and it was treated like it was unnatural, sinful, and disgusting. It was a thing you didn't do. Yet, everyone was doing it.
I had a first-hand view of the hypocrisy of everyone saying DON'T while DOING. I remember attending a fundamentalist Christian wedding when I was kid and stumbling upon all the bridesmaids and ushers making out and having sex behind the church. Yet, these same kids (they were older teens), acted like butter wouldn't melt in their mouths and talked the talk their parents expected of them.
The message about sex, nudity, a woman's body, etc was clear: sinful, bad, evil, etc. It would take me years to stop hating my own body. It would take a lot longer to realize sex was a natural part of life and nothing to be ashamed of. In my own life, sex is a vital part of my relationship with my husband.
When I started writing, sex, violence, swearing, etc were all things I was shy of because of my fundamentalist background. I was even shy about writing about relationships. My first stories were pretty superficial and dull because I wasn't willing to take risks with the storytelling. Finally, I stopped worrying about offending people and started writing my stories in the most truthful manner possible. That included the gore, the violence, relationships of all types, swearing, and even sex.
Yet, the fact that some people can read a book with tons of violence, death, and destruction, but freak out if there is a flash of romance or sex completely confuses me.
Sex is natural. It's part of life. It can be used (and abused) for various reasons. Sex is the natural part of a deep, loving relationship. It can also be used for recreational purposes. It's a stress reliever, a form of control, and sometimes both.
In the context of a horror story, sex can serve multiple purposes. A well-done sex scene adds to the story and doesn't detract. A good sex scene is NOT about <insert penis into vagina>, it's about emotion, the evolution of a person/relationship, and progressing the story.
Yet, I know if I reach a sex scene in a book where it seems out of place, appears to serve no purpose, etc... I'll skip it. In the same way I'll skip an ultra-violent scene, or a boring description, etc.
I hear from readers quite often. "Please tone down the violence." "Please less gore." "Please add more violence." "Please add more gore." "More sex." "Less sex." "More romance." "Less romance." Etc...etc..etc...
I have finally accepted that I must write the best story I can write. I need to include whatever aspects fit that story. Some readers may come along for the ride, others may not. Some readers will read everything I write, others won't.
The only thing I can vow is that I will do my best for the story, and therefore, hopefully, for the reader, too.