SHRIEK: AN AFTERWORD by Jeff Vandermeer

[eska]

... it is also a fair summary of the novel's conceit; this is presented as a biographical afterword to a book by the missing historian Duncan Shriek, written by his sister Janice.

Except that Duncan finds the manuscript before it's published - so when he feels that Janice is giving an inaccurate portrayal of his acts and motives, or of her own, he notes his complaints within the text.
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