"Eromanga Sensei" volume 9 by Fushimi Tsukasa. If you had just finished the anime series but didn't keep up with the original novels, you can stop reading now. The spoiler is on the front cover.
This entire volume is the reaction to the last line in volume 8, where Masamune proposed to Sagiri. Few months after that, volume 9 came with the subtitle "newlyweds life with Sagiri". Masamune and Sagiri did not actually get married in this volume for various reasons, nonetheless the text is exactly the kind of sweet stuff you might expect from a newly married couple, like "let's think about our children's names" kind of stuff. It was like that from beginning to end.
You might have thought that the sweetness early on was building up to a major conflict, which was the strategy taken by the other series about little sisters. There were no such conflicts in the first two chapters, but there is a bit of twist in the final chapter where readers get a bit of history about Sagiri and Masamune's parents. Ultimately turned out to be very sweet as well, if the first two chapters were milk chocolate, the last chapter would be dark chocolate. The masterful character developments that resulted in this chapter is brilliant, and all the meta jokes about these being light novel characters made it even better.
I found this volume immensely enjoyable, and really sweet. Feels like the ending is near, but maybe not in the next volume. I am looking forward to a happy ending.
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