Takamine Kiyomaro, a melancholy don't-care-about-the-world person, was unexpectedly assigned to look after a small demon named Gash Bell. He has no idea that Gash is involved in a fierce battle to choose who will be the demon world's king. All of the demons must choose a master on Earth and fight other demons until only one remains. Kiyomaro, of course, becomes Gash's master, and through their many conflicts together, Kiyomaro learns the value of friendship and bravery. Action, adventure, humor, drama, supernatural, and tournament are some of the genres.