He is centuries old, undetectable unless he allows it, and grants dangerous, forbidden magic to a target while guiding them down the darkest path. He looks like a man in a dark costume, but his mysterious abilities and inscrutable motives suggest he's anything but a human. It's implies that he was once human, but has since become. A former hero from 500 years ago. Experiments with L-bacteria/Labose, a plague that makes people infected with the plague into monstrosities when they die.