It's a story of a rural town.
There was a rumor in the town. Sometime ago, monsters began to appear ... And it was devastated.
One day, the shrine maiden was invited to the town by the residents. She performed necromancy with her disciples, where the spirit of the noble female appeared.
And the spirit told the story of how she died. Then, incensed with long-standing resentment, she was transformed into further mighty evil spirits. The evil spirit went out of control and tried to isolate the entire town into the Shadow world, including the inhabitants.
The shrine maiden made a barrier at the expense of her own life, and entrusted the "Phantom Mask" and "Miracle Crystal" to the disciples.
The one wearing the "Phantom Mask" becomes "Ayakashi", and you can see the evil spirits.
Those who have the "Miracle Crystal" can calm the grudges and save the world that has become the Shadow world.