She became so important to them that they wondered how they had ever managed without her in the past. And the longer she stayed with them the more indispensable she became, so indispensable in fact that their one fear was that she might some day move on.
He's really sort of the devil. He's completely emotionally detached. He has no empathy. You find that in psychopaths. It's about power with Voldemort. It's an aphrodisiac for him. Power makes him feel alive.
The chief role of the universities is to prolong adolescence into middle age, at which point early retirement ensures that we lack the means or the will to enforce significant change.

