The "author" in question was a relatively minor character, with the quirk of writing everything down as though it were a story. Near the end of the trilogy, he tells some others that he's already written the ending, and the bad guys are going to win. They respond that if the bad guys win, there won't be anyone around to read his book - so he changes his mind and frantically erases the ending as the bad guys close in around him. The character is never mentioned again.

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