An anxious young man who nonetheless has a good head on his shoulders. Extremely bisexual. Probably on the spectrum.

"Oh, he's definitely sexually frustrated." -Hyde

"If he'd calm down fer five minutes, we'd be home by now." -Riot

While Oz is a highly competent wizard, he's somewhat lacking in social skills--especially the ability to make friends. Don't worry, though; he's painfully aware of this fact every waking day of his life.
He's been known to cope with this anxiety via biting sarcasm. Underneath that, though, Oz has a good heart.