Saya Kisaragi is a seemingly-normal girl who is overly clumsy and kind. She lives with her father, the head of her hometown's shrine, and learns the "art of the sword" from him. She has to fight against the Furukimono ("Ancient Ones," or "Elder Bairns" in the English dub), the monsters that menace her peaceful town, with a sword left by her missing mother. However, as she fights against them, she learns more things about who she really is and her real mission.
The series is set in the same world as the other installments of the Blood saga, but features a completely different story and setting.