The story begins in a parallel world, where gods and humans exist together. In order to preserve the peace and quiet, it elected a new princess, which should serve God Hayagami at a special ceremony every 30 yearsBut only the girls from the Hime Clan awarded this honor, and when it`s time, there was a serious problem: the clan in the past 30 years have not been born a girl, and so the matriarch of the clan decides to send his own grandson Arat... disguised it with a girl. So during the ceremony Arata personally meets with the current Princess of Kokura,but one of the 12 sinsё - Kannagi on the plot plan makes an unsuccessful attempt on the Princess, which coincides with the state of suspended animation to survive a deadly wound. Since 12 sinsё except there were no other witnesses, all the blame decided to throw in the Aratu, declaring that he had deliberately changed woman, and killed the princess. So in a moment,Arata an enemy of the state, on the run, he wanders into a mysterious forest where accidentally swapped with Arata Hinohara of the Earth, an ordinary Japanese schoolboy. So " Arata of the Earth" is trying to escape from prosecution Kannagi and receives from the Matriarch Mikari sword Hayagami who wakes up in the hands of Arata.So in his visions he sees the image of a princess Kokura, which says that Hayagami able to heal all wounds and raise the dead, that is the only salvation for the princess, which will sooner or later die. Arata has to get to the princess and heal her, as her death will lead to strife and chaos in the world.However, on his way to meet a lot of Arata will be obstacles, but at the same time, enlist the support of new allies and friends.