A miko at Tenkai Shrine and the shrine's resident exorcist, Yayoi has been close to Matoi's family for years—she knows Matoi's parents, Shingo and Shiori, well enough that she's basically part of their inner circle. She's the one who actually handles the exorcism work around the shrine, and she doesn't hesitate to mentor Matoi and Yuma when they need it, whether that's advice, training, or just knowing what to expect in the field.
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