"Eromanga Sensei" volume 10 by Fushimi Tsukasa. Exactly as advertised on the cover, this volume is dedicated to Muramasa.
Muramasa is holding something that looks like a love letter on the cover, but this particular event didn't happen. Instead, she wrote a whole novel for the same purpose. The first half of which was already done by the beginning of this volume, and the remaining chapters describe how Masamune spent time with Muramasa at her school festival to help her complete the second half. The most fascinating premise about this was how this is a book written to target exactly one reader, and it was said to be on the same perversion level as certain chair story*. We can only imagine.
While this volume is dedicated to Muramasa, this whole series is still about Sagiri. Muramasa is definitely the focus of this volume, but Sagiri's presence can be felt around every other page. There was a really sweet dinner scene that shows Sagiri's progress up until now, and actually this entire volume is a reminder that Masamune also wrote a love letter in the form of a novel back in volume 1. There is no contest as to who is the main heroine.
The outcome of this volume was mostly predictable from the very beginning, but it was still great to see all the spotlight for my favorite left-handed character in this series. There is no hint as to what volume 11 would be, but hopefully we see more Muramasa.
* "The Human Chair" by Edogawa Ranpo.
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