He's a powerful sorcerer.
He is kind, caring person. Appears scary when he's angry. He's smart and slightly manipulative, he might threat you that he will stop his heart if you don't do what he wants for example, basically uses your weaknesses against you, but he wants to make you happy.
He says he wants to teach you 'naughty' stuffs but he doesn't mean anything perverted by it. It's more like he wants to spoil you a little, take you shopping, buying you stuff and sweets etc. 