The legendary dragon SuperNovaDragon Siegwurm-Nova, whose home is a completely different world from the Earth, has been transferred to Japan through a wormhole made by his friend. There, he is turned into a human girl, and unable to use any magic due to the lack of magic power on the Earth. He needs to find a way to return home. During the process, he has encountered different individuals, some help him, some become his enemy. At the same time, he has discovered a mystery linking his world and the Earth. What is the mystery, and can he go back to where he belongs?