Philosopher's Stone and Minerva

it is a world where the human world and the demon world coexist. The peaceful small country of humans called "Orin". In contrast," Orkinus" is a large country that controls the demon world. At the time of the coronation of the new king, the demon king "Orkus" suddenly appeared. The demon king "Orkus" defeated the former king and took the current king away. Minerva, a warrior, confronts the demon king, Orkus, in an attempt to protect the king, but she is unable to stand up to him and is defeated. A crack is about to appear between the two worlds...