The Creator had created Impthus out of the very essence of light itself. And so do all of his fellow followers. The Athlran glow endlessly, no matter where they are. They have a pair of white wings and their form radiates bright light, as the High Heaven itself.
At the beginning of life, before the Living World was created, the Creator had created only Felenthur and Impthus, that he made them both as brothers. One with the heart of darkness and one with the heart of light. Impthus was given the High Heaven with the Orb of Light. While, Felenthur was given the scorching plains, where soon, he transformed the plains into the Burning Hell as soon as he managed to made a plea to the Creator. A plea which he asked to create an ally for him. Thus, the Demon Princess and Princesses were born into the Burning Hell.
They have no souls, but they live. They are formless, but they walked. They are unseen, but they reveals. They walk the dark plains, but they show the lights. And they were given a chance to choose side. And yet, they chose righteous. And that's the Farons. Creature that walks the void realm.
A PC Conjurer or summoner, basically any mage whose sole purpose in life is summoning creatures to aid in battles and various situations, is cursed with a hex, and needs to find a way to undo the curse...before he goes mad, or his fellow PCs throw him out of the party, or worse.
Everything he/she summons, never goes away. So you'll have to figure out what the heck to do with that dire bear or fire elemental once it's done fighting the orcs for you. Eventually a caravan of bizarre creatures either annoyingly ends up following the summoner around, or they go off to cause mayhem elsewhere. Bad news for the poor spell-caster regardless.