User blog comment:Jopjopjop/Volume 19 Spoilers/@comment-24412159-20141121000829/@comment-4320546-20141121055743

Two things. One, the green fringe has been slowly disappearing over time going by the illustrations, so maybe it was originally dyed and is naturally going back to it's original state. Time wise in universe, it HAS been nearly a year since Xenovia was introduced.

Two, I wonder if Xenovia was an orphan or abandoned like Asia was? It would definitely explain the lack of a last name.