Kagemitsu Kumou is a farmer until he is brought to Lake Biwa, six hundred years before Laughing Under the Clouds, and made head of the shrine that shelters Botan, a spirit the Abe clan of onmyouji gave up its own members to summon. Only she can seal the Orochi, a giant serpent that wakes every three hundred years. Fighting beside Kagemitsu is Hirari Abeno, who calls himself the Abe family's failure for his lack of talent with spells and who has loved Botan since childhood. This Kamakura-era prequel shows how Hirari and Botan's story began.