Quote Originally Posted by Tifa's Boobs View Post
The Devil didn't do a very good job, since he later is trapped in a magic lamp and enslaved by high school students.
I know you're trying to be sarcastic, but I think this could be used as additional evidence. The devil could easily feign entrappment for a number of reasons, and the possession could be mutual. Isn't it strange that the principal of the school would be in possession of the devil? The item is gifted as a means of transferring forbidden knowledge, and done so unwittingly for a newcomer to the game.