Girl-library of supernatural knowledge is used as a holster by her key-master companion, to pull out (of her) a magical volume to read a verse from, to defeat whatever supernatural adversary they are facing.
Absurd stories and average (at best) execution. Characters try to be adorable with little success because their personalities are so shallow. Almost no character development and little continuity between episodes.
The only surprise was delivered by episode 9 which drastically changed the art style but only for that one episode.
https://myanimelist.net/anime/8915/Dantalian_no_Shoka
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