"Imouto sae Ireba Ii" (all good as long as we have younger sister) volume 14 by Hirasaka Yomi. This is the end.
Somewhere around volume 10, this series isn't focused on younger sisters anymore. This is a real shame since Chihiro is one of the best sister characters ever, the kind of all around perfect person who would help her rival to win the same man that she herself was going after. Chihiro did get a reasonable ending in this volume, and a different part of the ending was rather true to the title of this series. But in the end, it was all about Itsuki.
The real ending was Itsuki's award ceremony for his second hit novel, in which Itsuki gave an inspiring speech about embracing change and becoming the main character that you always wanted to become. This speech encapsulated the two best features of this series: the unexpected character growth and all the backstage details of the light novel industry. The insider info bits especially, I felt like I have witnessed five years of a light novel author's live condensed into mere 3000+ pages.
This has been a great series covering a wide variety of topics. The premise might seemed predictable from the start, but this is really a unique series that is totally worth reading again.
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