Almost two years ago, this gem was created. Now i quote here, because i hope you or someone else has a skin fix for her cursed backside xD
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Yeah, that's built into the texture I'm afraid, though you could load the texture into an editor like Photoshop or GIMP (free) and edit that out. I have edited my own textures already, I have a character I really love her look, but her nipples were fugly, so I ripped the nipples off another female, and edited them into the one I liked and it is all good now.
Go to the Surfaces tab, and with some searching, you will find her texture. When you see the body texture, click to change it, select BROWSE and you will find the folder where it exists. You can then copy it, and edit that out if you wish, then save your fixed version inside the same folder and apply it instead.