You know, I think doing a screamo scream might scare the shit out of anyone who has just penetrated you/ been penetrated by you. It's like a battlecry, but scarier.
I think, if it's a guy, it would be funny if as soon as he's in he starts screaming like he's terrified.
Or like he starts howling in pain and then say something along the lines of "Jesus! What do you have in there? Razor blades?!!"
You could wait until your both really into it, squeeze your eyes shut tight, and then say "Oh, God, mom, you'll always be the best."
Another fun one is to start screaming "No, daddy, no! Please don't!!!"