Questions to LJ, Chiefly on Porn

I've been trying to write some porn, but it's turning out a little boring. I think I'm somewhat burnt out on writing sex scenes. So, I was hoping you could help.

My first question is stylistic. I find it hard not to use the same verbs and adjectives and metaphors over and over again. How do you keep your sex scenes fresh and interesting? Do you notice if an author is repeating herself? Are there things you like to see over and over? Words you hope to never see again?

My second question is about what makes erotica hot. I'm talking about fanfic PWP here, not sex in a longer story or non-fanfic erotica. But if you read a 500 word mouthful of fanfic porn, what makes it hot? For me, the thing I most need is for the sex to illuminate something about the participants's relationship. How about you?