I don't see how it can be a fake. Look at the birthmark on her breast. Look at the mole on her right forearm and the two moles on her left hand/wrist.
How could someone have inserted the bottom of someone else's breasts and nipples AND removed the shirt that would have been there if she wasn't holding it up. I guess it's possible if the top was see through and all of that was removed, but then why would her hands be raised if she wasn't holding up a top?
I choose to believe it's real.