[ Jack frowned at the revelation of a fight with their roommate, regardless of what it had been about. ]

Well, sure, but he didn't understand how the toaster worked at first either. Lots of things are different between his world and ones like ours. As for "wrong", obviously we don't think so, and since neither of us are dating Wan, it's just a difference of opinion.

[ Not that he seemed especially happy to have heard that -- the Avatar seemed pretty chill when it came to most things -- but Jack was trying to keep an open mind. Still, he could understand why hearing those things might have prompted Zatanna to call him in the way that she had. ]

Maybe someone just needs to explain it better to him.