KakaretteKosplay, or Bridgette Rockette, did a bodypaint-based Krystal cosplay back in March for MomoCon 2012. I believe she said she created the costume very quickly using materials obtained very near the beginning of the con. There are only a few photos, but I've already contacted her for more and additional information.
Thanks to whoever submitted this info! (I'll fix the form so you can be properly credited in the future.)