Oooh, hard to say, hmmmm, besides DEATH (cuz he loves kittens), might have to be Sam Vimes, and of course Esme Weatherwax. Too hard to pick just one.
Duke Vimes, because he does what he knows he has to, and also Loves to Tweak the noses of the pompous out of joint. Oooh, just realized they all three have that same sort of thing in common. Whaddya know.
Aha! So, Bob's yer uncle... very clever.