A boy who is fascinated by Japanese folklore dies unexpectedly one day. While dying he made a single wish "To be reborn as a yōkai". However, he didn't become a yōkai, in fact he found out that he had become the grandson of Abe no Seimei, greatest onmyouji of Japan. Will he walk the same path as his grandfather and become an onmyouji or does fate have something else in mind for him...