"You'd be surprised how much anyone was observed at any given time."

But that seems like a terrible subject to go down, and he casts about for a new line of conversation, ends up on: "How's Rodolphus?" ... Which then, seems like an equally bad topic, and Severus looks a bit like he wants to do something like pinch the bridge of his nose, but instead gets some more pizza so he has something to shove in his mouth to prevent himself from talking anymore.