Mawang

Demon King, he is an individual that only can be killed by a hero. He is also responsible for managing the demon realm's safety, and due to his long lifespan he has mastered all weapons techniques and arts. Furthermore, he was also the one that recruited Deon Hart, a human that he misheard as Demon Arut to become the specialized Zero Corp's Commander after witnessing Deon "kill" the Hero.