It's all about the glasses.

There are elements of supernatural battles and so on, but in the end it's all about the glasses. This is an anime for people who seriously like girls with glasses, even if they didn't realize that they had such tendencies before. Glasses bits aside, the battle scenes were very well done, and the story has some unexpected turns to keep it interesting.

Based on novel series of the same name, the anime contains a lot of original elements, and is pretty much superior in every way. The main common trait between the anime and the novel is the love of glasses, and confusing details about how youmu works. I would recommend watching the anime, but skip the novels.

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