Hang-Ups On Writing Sex

I want to submit something to this anthology on gay modern-day fairy tales. Only when I read the submission rules, I saw whatever I submit must have sex.

I know, I know, the novel in progress is urban fantasy, but I managed to avoid plot points that leave me no choice but to write a sex scene. Mostly because the MC is in love with someone who is too pissed with him to have sex. Also because the story doesn’t actually have anything to do with sex.

Point is, I have never written a sex scene before and I haven’t a clue where to begin. Especially gay sex. I mean, I am a girl and I am straight. My entire knowledge of gay sex comes from gay romances. They may not be the best source of info.

Thing is, I really like the idea of retelling a fairy tell in modern terms.

I figure I’ll keep a nice level of sexual tension going throughout the whole story and actually let them have sex once or twice. It’s going to be around 5000 words – there isn’t much room for lots of sex scenes anyway. And foreplay is the best part of sex, right? Well, they are guys, so maybe not . . . But foreplay will keep the story pretty sexual even they are not having sex. Kissing, touching, flirting.

It’s just – how do you write a sex scene?

Anybody got any advice?