The encyclopedia is a large, hardbound book with a light brown cover and beige-white pages. The title is underlined and printed on the front. No author is included. Four parallel lines border the cover. Two stylish accent lines are included: one below the title and a smaller one at the bottom of the cover above the border. The cover is worn on the corners, showing its age and/or frequent use.
PlotWhen Kasuga brings an ill Oryo to Aoi at the Annex, she provides both the Yokai Medical Encyclopedia and the necessary medicine. Aoi reads the encyclopedia to learn that snow women need to eat cold things when sick. She takes that to mean ice cream and sorbet. Having a lack of ingredients, she first makes ice cream with tofu. She next makes cherry-flavored ice cream. In addition to traditional medicine, Oryo recovers from her fever after these two dishes by the next day.
While Oryo is still her patient, Aoi references the encyclopedia again in regards to helping the weak and injured Akatsuki after his fight with Suzuran. Generally speaking, it is believed by Oryo that Aoi's cooking heals spiritual energy, so anything Aoi makes should work. As Akatsuki is against Aoi taking care of him in the first place, however, he does not eat her first offering of oyakodon (a Japanese rice bowl dish with chicken and egg). That same night, Aoi, in a fit of frustration at his stubbornness, blends a vegetable smoothie and forces him to drink it. His spiritual energy readily returns and he immediately shifts back into human form in order to escape her.
"There are three main ways to treat injured earth spiders. Treatment one: Leave them be until they heal. Treatment two: Give them spiritual power treatment. Treatment three: Have them take in things with high spiritual power."
"Fever in a snow woman. They can run a fever if they're near fire for too long. To treat it, just cool them down. Avoid warm food. Have them ingest cold water and food. Icy snacks especially can help."