If she doesn't want to do it, end of story.
For many people who don't want to model/perform, it's not about the money.
She has a nice face and body, and great boobies. Her only flaw appears to be the appendectomy scar, or whatever that is on her tummy.
Just having content of a good looking model will not make you money. If you have never marketed a site before, be prepared to get schooled in the hard cold business of competing in an over-saturated market.
If you talk your GF into modeling with promises of certain riches, imagine what she will feel like months later with pictures all over the net, and just a trickle of money coming in. You could lose your site and possibly your GF.
Also, twice a month updates will not do much for Member retention. Try twice weekly, and if you don't have video too, forget about it.
You have a nice girlfriend. Be satisified with that. Trying to talk her into something she has already expressed that she is against is not a good idea, and may even cause her to question why you are with her.
Finally, can you post some full nude shots - need to see that cooter too for a complete evaluation...
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