I don't think it's that fuzzy, because even if you gave consent at one point to be photographed naked, that doesn't mean that the person having access to the photos can do anything they want with them. I mean it's one thing to send a nude pic in a sext and it's another to upload the pic to the internet with all your personal information.
There was a great interview about this last year in a Canadian radio show: http://www.cbc.ca/q/blog/2013/06/13/end-revenge-porn/