I had a recent experience and the person liked having a firm hand over his mouth, to keep him from talking, while my other hand was busy.
It was an interesting time.
And there is a bunch of porn dealing with this. He wanted me to "shut him up".
http://xhamster.com/movies/954425/hand_over_mouth.html (These are very tame and just a few examples)
For once, I was pretty surprised at how aroused this made him feel.
What are your thoughts about this? It was fun. Just wanted to discuss it some.