One hundred forty years ago, the Impure King terrorised Japan, spreading disease and killing forty thousand people. Eventually, its heart was split into two by the monk Fukaku. The two halves of the heart becoming known as the left and right eyes of the Impure King. The left eye was stored in the True Cross Academy's Saishinbu while the right eye was stored in the Kyoto Branch Office under the watchful eyes of the Myōō Dharani.
Saburota Todo stole the left eye from the True Cross Academy's Saishinbu and manipulated Mamushi Hojo into stealing the right eye from the Kyoto Branch Office. He implanted them both into the sealed body of the Impure King that had laid dormant at the Goma-do, awakening it.