When Keika receives a request to vanquish youkai, her younger sister, Hatsuka, is already out on another quest. Determined to set a good example for her less disciplined sibling, who often fails to show up to training, Keika visits the village Shinto priest who made the request. This priest tells her of a giant monkey youkai who has led other youkai on a rampage in and around his village. She confidently accepts the request alone, believing that her powers as a priestess would help overcome them...

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