Rokuro Enmado is a young boy who used to be a powerful aspiring exorcist, before a tragic incident left his friends dead and made him abandon the profession. One day, he has a fateful encounter with Benio Adashino, a girl around his age and a well known exorcist from the east. According to prophecy, Rokuro and Benio are the "Twin Star Exorcists", and are destined to marry and have a child known as the Miko, which will be the ultimate exorcist and the reincarnation of Abe no Seimei, capable of cleansing all evil spirits, or Kegare, from the world and ending the war that has lasted over a millennium.