User blog comment:IamJakuhoRaikoben/Chapter 281: Malice is Concealed by the Curtain of Night, Review./@comment-86.27.235.200-20120504193706/@comment-79.85.46.28-20120504213322

(sorry for double post) the wikia contributor (the first one) is probably refering to the fact that Ultear had a big scar on her back instead of her GH crest...

However, I don't exactly know how they can remove the crest, but it's not the first time that it's done without letting any scar, there was already Gajeel, actually, and also Juvia (yet we didn't see where her Phantom Lord crest was). Which makes me think that for Ultear, she did that on purpose so that the memory of her sins won't be erased, because she didn't want to forget about the atrocities she has committed, or something like that.