If it's a scream it involves a weird opening of the back of the throat and a high-pitched noise. Which would make words difficult. (This is a problem that annoys me in all fics, fan and original, by the way.) So if you can pick a word that suggests what you mean that isn't the horribly clichéd scream, I'll be happy.

And yes, porn fibs. For a start, it's actually possible to have sex that doesn't begin with breast-groping, continue to a blow job, move on the cunnilingus and then cycle through three different sexual positions.