Going Postal, Making Money by Terry Pratchett

Two later Discworld novels, starring reformed crook Moist von Lipwig, pardoned by the Patrician in order to revitalize the city's moribund postal system and, later, the royal mint.

Oh man, so much love. Not the book-shaped awesomeness of a Watch novel, but they have a really similar feel to them. Moist is clever as clever can be, but kind of broken in the way he can't live without Adrenaline. Pratchett does such a good job with him – I mean we know this guy, right, the trickster with a heart hidden away back there somewhere. But Moist is complicated and kind of messed up in really quiet ways that only he ever calls himself on. These books feel, I don't know, a little grown-up Discworld, in the really good way where Moist has this awesomely real romance.

Which isn't to say they aren't hilarious books, because they are. Plus Vetinari! Everywhere!