Three youkai or supernatural creatures, Bem, Bera and Bero, who arrive at a large coastal city and come across an evil atmosphere, which was brought about by immoral behavior by humans and mischief caused by monsters and yōkai. They therefore decide to stay in the city, fighting against other monsters and yōkai which attack humans, making a few friends along the way. Even though the three yōkai are often abused and discriminated against by other human beings due to their appearance, they still strive in protecting the human populace of the city from other monsters, one day hoping to become human beings in return for their good actions.