User blog comment:IamJakuhoRaikoben/Chapter 457: Naked Battle, Review./@comment-24228963-20151019061227

Still hoping for Brandish-Karen theory. Remember she was brought up by Angel/Sorano a few chapters ago. She's a Celestial Spirit User like Lucy and Layla. Based on one of the colored pages of the manga, Brandish has green hair which is the same as Karen. The way they dress up is very close and their appearance is similar. Maybe Layla was somehow related to an incident with Karen or Brandish.