"Biburia Koshodou no Jiken Techou" volume 6 by Mikami En. This volume covers a case where the old robber from volume 1 is out to steal Dazai Osamu's "Bannen", the same book that he was trying to steal in volume 1. This volume feels redundant in many ways.
Volume 6 started out with a continuation of the character development between Shioriko and Daisuke from the previous volume, and surprisingly managed to fold all the gossip as a clue for solving the mystery this time. Otherwise, the Bungaku Shoujo series does better on this front, I wasn't expecting romance from this series.
What I was expecting was more trivia on old books, and this volume described a different edition of "Bannen" -- Dazai's personal copy. Not sure if this bit is historically accurate or merely fiction, but it's interesting to imagine the possibilities. Also interesting was how Dazai actually published a book under a different name[1]. The best highlight for this volume is discovering this extra story that might have been buried otherwise.
Other than bits of Dazai Osamu trivia, this volume feels redundant with respect to other similar series, and redundant with respect to earlier volumes. I feel obligated to follow this series to the end since it's supposed to end soon, but I wonder if I will read them again.
[1] http://www.aozora.gr.jp/index_pages/person974.html
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