Here's another idea. Very simple and straightforward.

Watch her. Have her assume a position you particularly like, one that is comfortable for her, but exposes her. (Naked of course!) Then just watch her. For at least 5 minutes. They will be a long five minutes for her and she'll have to resist the impulse to squirm. When the time is up, tell her how proud you are, how much you enjoy seeing her display herself for you... this can eventually turn into watching her masturbate for your entertainment.

Yep, turned on again. I need to stop posting in this thread!