I just think the picture seems off and if you zoom in a little it's blurry on the sides. Who knows, it was just a guess that she does.That's photoshopped? If you're referring to the curvy lines to the right of the pic, I thought that was draped fabric? It seems to match all her other stomach pics pretty consistently. I wouldn't have suspected photoshop.
I do find it strange that there's next to no info about her anywhere online though. According to her instagram, her name is Kayleigh Smetsers, however the only Kayleigh Smetsers I can find much about online is a design student/photographer/actress, from The Netherlands, who definitely looks nothing like her.
Seems odd.