RAZAZI OF THE SALAZAR

In a world with pirates and warriors who fight with almost every kind of weapon, even toilet paper? You'd expect no one to be too different BUT there is a certain group of people deemed to dangerous for this world...."Oni's children" or children of the devil. These people possess power that can either rival God or themselves the first person ever named "a child of the devil" started a war against the Kai (Gods of the earth) and "The highest beings" this person's actions is the result of these mostly harmless people being deemed "Devils" but how can just a 12 year old end all of this?