WN/Satanael

The Ultimate Skill Wrathful King Satanael [憤怒之王 (サタナエル), Fundo no Ou (Satanaeru)].
 * It could be called as Magic Essence Breeder Reactor since it works by converting the user's Wrath or rage into Magical energy, thus, as long as the user's still mad, the user could have infinite Magic Essence.