"There will always be cracks in the walls rats can squeeze through," he admitted with a curl of his lip. "They can nibble on the concrete foundations I've set down, but it will take a lot of effort before they get anywhere, and they haven't got the numbers to make any real damage anyhow." His smile was in full now, gleaming. "Yes, they can cling to their pathetic resistance. Let them raise their fists in the air and vow to bring me down. They've been doing it for years, and their numbers continue to dwindle, and I'm still here. Not very good for morale, is it?"