Being the highly trained observer I am the dark spot at just under where 9 o'clock would be in the belly button jumped off the page to me.Morning.
I'm not seeing any crud. She's got a big navel with one of those "not exactly an innie or an outie" configurations but no crud that I can see.
Anyway, that wouldn't be a knock on her modeling abilities. It would be a knock on the stylist for not catching it early and the photographer (to a much lesser extent) for not catching it in front of the camera.
Or it's the floater in my eye. Lol