The influence for them was the movie The VVitch, hence the subtitle "do you like the live deliciously?"
The idea being that they are higher powers you can worship/petition. So instead of the traditional Cleric role, anyone can choose to follow one and live by the principals of that being. But they are also left rather open so as to inspire people to take them and run with them.
So there is no "canon" for them. Yet. I'd have to run a game where a player reached out to one to really figure that part out.