Fiction.
From Kurt Vonnegut’s God Bless You, Mr. Rosewater:
Mushari dutifully went looking for a copy of the book for his dossier on Eliot. No reputable bookseller had ever heard of [Kilgore] Trout. Mushari made his last try at a smut-dealer’s hole in the wall. There, amidst the rawest pornography, he found tattered copies of every book Trout had ever written. 2BRO2B, which had been published at twenty-four cents, cost him five dollars.
[Mushari] was witless enough, too, to imagine that Trout’s books were very dirty books, since they were sold for such high prices to such queer people in such a place. He didn’t understand that what Trout had in common with pornography wasn’t sex but fantasies of an impossibly hospitable world.