Long ago, the Emperor possessed great mystical powers. Now, a young boy wonders if he will have them as well.
With no memories and only a rose-shaped scar on his forehead as a clue, he ponders his legacy while on the run with the girl who rescued him from a group of armed warriors. She takes him to a scientist who identifies Rose as the Emperor's clone and believes that this young boy must assume the mantle of leadership. But opposing forces with their own agenda have created another clone from the Emperor's DNA...and now the struggle for power begins!

The story revolves around four main characters - regular old 10th graders, until they are chosen by a slip of Tatsuki's tongue to be the human masters of the ancient Four Gods! The four teens are chosen to battle and vanquish the servants of the Demon King, who has escaped from the celestial world to wreak havoc on Earth.