Demon born and demon bred, Zavid Frost doesn't have much use for humanity. For countless centuries, he's been locked in Helheim to be used in arena fighting. He is semi-grateful for his release, however does have problems with trading one prison for another.
Centuries ago Zavid made a deal to be imprisoned in Zarelda's place, knowing she would not be able to survive their intentions. The entire time he was under the belief she was safe, unfortunately upon escaping after meeting Nick Gautier, he found out Hel had gone back on their deal and his sister was killed long ago.