His mouth tightens and he says rather dismally (enough that it affects his tone just a bit), "I'm hard to mistake, unfortunately." Not that Jack wouldn't be hard to mistake for most people, but Zel's too broody to realize the potential implication of his comment.
"I was forced to be come this, turned into a chimera by a mad bastard masquerading as a holy priest, but possessed by the Dark Lord- the leader of the mazokus. Now I'm demon and golem too- that's why I look like this." He tugs the hood up again reflexively from how it was slipping down, exposing one of his distinctly long pointed ears.