The Ascension of the Demon King

In a world where Demons wreck havoc through Dungeons, Keith was an F-rank Hunter and was notorious for being lazy and mediocre.
But fate had other plans for Keith. In a near-death encounter with a powerful Demon, he unleashed a power that he never knew existed within him. He was called a Demon King, a title for beings that were half human and half demon. His newly acquired power gave him incredible abilities that can surpass even the strongest Hunters.
Despite all of these, Keith's journey was far from over. He discovered that there was a greater threat lurking in the shadows, a force that threatened to destroy the entire world. Follow him as he battles these great dangers while discovering the secrets of both Demons and Hunters.