Coco is a kind and daydreaming daughter of a dressmaker who aspires to become a witch; however because only innate magical users can practice and use magic, she has to give up on her dream. One day she meets a witch named Qifrey and after she witnesses how he uses magic (by drawing magical runes and using magical ink), Coco accidentally casts a spell that turns her mother to stone.
As Coco does not know which magic spell she cast and Qifrey is tracking the sinister coven that could be behind the incident, he takes Coco as his apprentice in order to undo the spell and allow her to fulfill her dream. As it is gradually revealed, the coven in question — the Brimmed Caps — have taken an extraordinary interest in Coco, hoping that she will help them revive the free use of magic, which was outlawed because of the atrocities committed with it in past times, with some of their repercussions still enduring in Coco's world. Because rune magic can be effectively made by everyone, the Assembly carefully watches over any abuse of it, even going as so far as to erase the memories of any uninitiated when they discover this secret. Thus, as Coco immerses herself into this new, wondrous world, a sinister plot begins to thicken around her.
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