In the world of The King is Dead, the Satanic "Holy Panoptic Church" is the only authorized religion in the vampire-held lands of Malleus and Erebus. From the perspective of the Panoptics, what we would call demons and devils are the chosen messengers of their God, while what we would call angels are the vile tempters of the anti-God. Because of this understandable in-game persepective, I've been calling demons "angels" and angels "demons" in the game materials.
Is this a good idea?
I don't really like setting-specific jargon. I love the Forgotten Realms, but I rarely try to remember all the different regional names for gold pieces. My eyes glaze over when I read about Empire of the Petal Throne. Is this subtle switch in naming conventions just going to lead to confusion for the players?
What do you think?