about king bahamut's question: Yes, Jez is a time mage, but also a blackmage.
About GG's question: in that part that Zidoran changed, Jez ran away to commit suicide. He wouldn't have done that if Britney had shown up. I may have misunderstood that but my guess is that Britney wasn't there to break up the fight (at least in Zidoran's changed part).