They are there among you, in the forgotten corners of your shining city: the punks, the artists, the destitute, and the dispossessed.
If they have seen god at all “he” has not been kind to them. And now, they are banding together (at least in one city), fighting for mutual support but not under David’s banner. A demon has reached them first.
They are not evil, they are not cruel, but they’d rather be damned than follow your rules.
While you are welcome to introduce your own patron – I would pick a renegade Djinn of Fire who is under Lilith’s protection.