Gifs/videos of girls clenching their vaginas, particularly (but not exclusively) during orgasm. Assholes and dicks are also welcome, just as long as you are not one of them.

Camgirl has a huge orgasm with contractions
Vibrators really get the job done
Her new toy did the trick...
Janice Griffith with a fucking machine
Pussy breathing
Pushing the cum out (x-post from our friends over at
I'm about to cum...I'm cumming...AH! (3 anal contractions in 4 secs @ 1:03)
Blowing Kisses
Though you can't see the actual genitalia, her butt is definitely revealing some clenching
Miss Violet trembling, garnished with grool
A wink to end all winks
Clenching tight
When the wink stops you in your tracks
Her powerful orgasm