"Biburia Koshodou no Jiken Techou" volume 7 by Mikami En, with the subtitle "Shioriko-san and Endless Stage". This volume completes the series with one of the most famous works: Shakespeare's First Folio.
Just a story based on the history of the First Folio would have been fantastic, and the author took it to the next level with not one but two cunning auction scenes, an interesting analysis on book sizes, and a long running revenge scheme that took 30 years to complete. This last bit is the result of obsessive old men plotting against the next generation of booksellers, and also explains the disappearance of Shioriko's mother. Most loose ends were closed with this volume, and the series is completed with Daisuke's marriage proposal to Shioriko.
The 30 year old revenge also exemplifies a problem with this series: most characters in this series come with an unhealthy level of obsession for books. For this volume, this obsession manifested in the perverted revenge scenario, compared to the more straightforward criminal acts in previous volumes. This is a series about the wonders of the antique books and does an excellent job in highlighting all the details and the intriguing histories surrounding those books. In comparison, pretty much every character who handles those old books were all unpleasant in one way or another. It was easy to appreciate the books, but not so easy to identify with any of the characters.
After the two year gap between volume 6 and volume 7, and after having read through other light novel backlogs, I finally brought myself to finish this series. Volume 7 is much more enjoyable than volume 6, and overall I really appreciate all the other books that were highlighted in this series. This might not be a series that I would read again soon, but the upcoming anime might be something to look forward to.
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Next (2017-07-16): "Biburia Koshodou no Jiken Techou" series by Mikami En