In one of my stories, I've examined the idea of Willow Rosenberg picking up one of the Blackened Denarii (from the Dresden Files; basically allows a Fallen Angel to rent out space in the 90% of your brain you don't use, making you one bad sorcerer). That's kind of an obvious mix, but what would happen if Dawn Summers (the sweet, kind, overly gentle Dawn) were to become a Denarian?
Would she become uber-evil (they say the greatest cruelty comes from the greatest caring, after all) or would she have the strength of will to remain untainted by the Fallen?
Well, you tell me!