Although I can’t say much about crystal without spoiling a few things, I can say that she is a complete sociopath. She does not care for anyone’s feelings and she has very little morals. She will do anything it takes for power and is the type to act nice just to stab you in the back (literally). She has magic that can be used to control the monsters from the other dimension, which she uses for either her own enjoyment of watching a city burn or just to do her bidding.  

 Her voice sounds both powerful and manipulative. She can sound sweet and nice but once she either gets pissed off or reveals her true self, she sounds psychotic and unhinged.