His family was slaughtered by demons and sworn that their deaths would not be in vain. He d ecided to join the Squadrent until he could find those demons but he never could find them so he's been stuck with the group called the Squadrent. The demons also caused an explosion to occur at him and his family's home after he saw his family dead and ran out the house the house it self crumbled as the impact of the explosion hit Ace and his face was scared from then on. All of his friends looked at him like he wasn't a human being and he was lonely but found the Squadrent.