Jacques the Fatalist and His Master by Denis Diderot
The main subject of the book is the relationship between the valet Jacques and his master (who is never named). The two are traveling to a destination the narrator leaves insistently vague, and to dispel the boredom of the trip Jacques is compelled by his master to recount the story of his loves. However, Jacques's story is continuously interrupted by other characters and various comic mishaps. Other characters in the book tell stories as well, and they, too, are continuously interrupted. There is even a "reader" character who periodically interrupts the narrator with questions, objections, and demands for more information or detail. The tales told are usually humorous, with romance or sex as their subject matter, and feature complex characters indulging in deception.