Given how everyone in this game is depicted as being fanatically loyal to their faction, I read this:
The heroes and villains of Warcraft stand larger than life, even in a world engulfed by constant conflict. Below, we've collected the personal histories and war stories of Azeroth's paragons. Will you fight beside them, follow them...or topple them?
This got me thinking: Which of the 11 classes do you think would be the most likely to be "The Resenter"?
http://tvtropes.org/pmwiki/pmwiki.php/Main/TheResenter
I would say either a Shadow Priest or a Death Knight. There's a lot of theories about how Shadow magic is powered by negative emotions since it shares a lot of similarities with Sha, plus, the religion of the Forgotten Shadow revolves around being on your own side, striving to become a God yourself (as opposed to the Light where Priests are subservient). DKs should have been laid to rest & instead ended up enslaved by the Lich King and are always talking about suffering in general; not to mention they seem to hold a strong hatred for authority in general given the betrayal they suffered by the Lich King, and even still they find themselves distrusted and hated by their factions.
Possibly a Monk as well, given how different their philosophy is...