Smilla, Harvey and Maude - Three awful people who somehow managed to create a pretty good thing.

Harvey and Maude founded the town that is now Rover's Crossing. They bought a bunch of demon slaves to build the place with the promise that it'd eventually be a safe haven for demons like them, because that's not hypocritical or anything.

Maude was originally just a merchant who picked Harvey up by chance shortly after he became a devil. Armed with her new devil companion and his very high ambition level, she decided she was done being a lowly nobody and got them involved in slave trading and other, shadier business.
I guess Harvey quickly got fed up with always being on somebody's hit list for trading with the wrong people. As soon as he had the funds for it, he left to do his own thing, and Maude tagged along. Building a town from the ground up didn't seem like too difficult a project for Harvey who had been used to owning and managing a lot of land, a plantation and shares in several companies while he was still a mortal human.

Smilla came in later while the town was in a pretty critical state and offered her help getting things back on track since she herself needed somewhere to stay at the time. Smilla is, I suppose, as close to nobility as you'll get in the demon world, but doesn't really like to rely on that. Prior to this she had spent her life mothering a whole lot of children and being what I can only describe as a total gold digger. In other words, she had quite a lot of money and investing in this town wasn't a big deal for her. She grew quite fond of the place, though, and ended up sticking around. Even in present day I think she still owns more of Rover's Crossing than Harvey does.

In current Rebound times Maude died a long time ago, but Smilla and Harvey are doing just fine.