You know, I was thinking about the reason why Millia was the only one to maintain a humanoid form, while everyone else who had demon possession (Alpha and co. included) turned into a deformed mass of flesh. If we assume that the mutation are because Anos blood (even in such abysmal quantity) is just too powerful for any non demon to withstand, then, doesn't that mean that Millia was actually very compatible with demon blood, more than anyone else in that setting? If we also consider that she managed to keep her sanity despite enduring experimentation and abuse for four years (which is indicative of great mental fortitude, then doesn't that mean she has the potential to become quite OP herself? Now I'm truly awaiting for the follower showdown!