Baron Malignor II

The Dark Lord Malignor ruled over his country through fear and subjugation, but was at the time just a mortal.  Wanting to secure his legacy, he fathered a son, and from his earliest age he taught him everything he knew about being an evil overlord.  After decades of his particular style of rule, however, he finally absorbed enough of his subjects' negative emotions to ascend into a Terror Elemental.  No longer bound by a human lifespan or the need to uphold a family line, he saw little reason to keep his son alive--even worse, he saw him as a potential threat.  The dark lord had built for his son on his Eighteenth birthday a castle of his very own, along with a tiny barony to rule over, but this was not done out of love.  The castle was little more than a dungeon of deadly traps, and with no reason not to trust his father, on his first day of baronhood the young man blundered into a particularly gruesome crushing pit trap, never to be seen again...
...Until he awoke at MSF High, in a dorm room styled much like his keep.  Not knowing the difference and assuming that he had simply walked into another room of his castle, he explored Mahou City under the impression that he was its undisputed ruler.  Given his peculiar upbringing, with all of the trappings of evil but none of the actual lack of morality, he mistook the friendly and helpful nature of some of the students to be slavish cowing to his will, while they in turn saw his cartoonish "evil" appearance and demeanor to be an overwrought act.  They led the young Baron to Miss Megumi, who was able to discern his nature, but did not reveal it to any of the students, for fear that they might "heroically bully" him, as such a villainous young man would be the target of dozens of potential gallant heroes.  Instead, she told her students that he was a skilled method actor, and convinced some of them to take up roles not only as those who oppose him, but sometimes as his loyal servants, in order to understand the workings of an evil overlord.  Baron still remains under the delusion that he controls everyone around him, and even when he is cast as the villain in Miss Megumi's plays and invariably defeated by the heroes, he will simply pick himself up, dust himself off, and return to his daily schedule of bossing people around, kidnapping princesses, and laughing maniacally.  Megumi feels confident that someday Baron will be swayed by one of the other actors' heroic speeches, and if he ever realizes the truth about what happened to him, one way or another once the Baron graduates his father will likely have a lot to answer for.