Choujin Densetsu Urotsukidouji

Legend has it that the human race is not the only dominant civilization living on the planet. Two other races exist on this planet: the Makai (a demon race) and the Juujinkai (one half-man, half-beast race). Once every 3000 years, a great being referred to as Choujin (Overfiend) will emerge and convey great all three realms in the world. In present-day Japan, after 300 a lot of endless searching, a Jujinkai named Amano Jyaku has discovered the use of the Choujin inside senior high school slacker Tatsuo Nagumo. These days, Amano - along with his sister Megumi along with their sidekick Kuroko - must protect Nagumo with his fantastic new girlfriend Akemi Ito in the Makai, who think that Nagumo isn't Choujin, but an evil entity bent on destroying all living beings on Earth.