OP here. Yeah, this ended the relationship on the spot. Especially with how I reacted to it. I believe my exact words were, "no! That's *expletive* gross!" She rebutted with, "it wouldn't be so bad, we've seen each other naked several times before." Referring to her uncle. That did it for me. It's not as bad as pedophilia, they're only a few months apart, he's older, but both over 18. Still I can proudly say she is my ex-girlfriend now and can do whatever the hell she wants with her uncle. This was literally the first red-flag I'd had in the three months since we've been dating. I was all for filming a video, and didn't think it even needed to be said that we'd be using a tripod, or perhaps setting the camera on a shelf, apparently, she had other ideas. It's too bad too, she was actually a decent girlfriend. Ah well, I'll cut my losses and move on.