He might sniff at you, but he won't hurt anyone unless he thinks they're out to harm me.
That's kind of a hard question to answer. Where I'm from, witches and warlocks don't really have schools of magic. We all learn basic conjuring, enchantments, hexes, and protection spell. As far as specialties go, I'm exceptionally good at conjurations, summonings, and I have a knack for necromantic rituals, but I don't like to use them unless there's a damn good reason to.