I know this is an older thread, but I have to say for you single guys out there a nice provacative picture leaving something to the imagination is preferred. I really like undone jeans or a towel where I can see a good body shot and maybe a peek of the groin area, no cock pics!
That. Cock shots turn me off and I actually ask that they not be sent. I do want to make sure it falls well within the middle of the pencil to forearm range, but a verbal affirmation will do.
I don't think I'm a romantic or anything, but I do like to like my/our partners. if it's just about their dicks, I have several dildos.
Saying yes opens up more possibilities than saying no.