Caolán is a devil who was tasked with keeping a watch on the new monster hunter. He is kind of a double-agent, providing information to the humans and the Demon King based on who he thinks will win, changing sides consistently, or at least he was, but something happened around the same time that Owen ran away that caused him to change. Quinn is certain it's the same event, but she doesn't know what exactly happened to make them both run away from their previous responsibilities. Now, he's completely on the monster hunters' side, though that doesn't mean he'll stop routinely messing with his favorite humans.