"Bit more than a century." The Master pulled the pencil from behind his ear, scribbling down a notation on the side of the schematic.
"I think I'm beginning to understand why you like humans. A little," he qualified, looking up a the Doctor again. "Some of them are just rather remarkable, aren't they? Most of them are irritating at the best of times, and downright infuriating most of the time, but not all of them."
He paused, tapping the end of his pencil against the paper a moment. "And some of them I'd be better off just getting rid of, if someone didn't keep taking away all my toys."