We had a teacher at school who used to poke her sharp nose forward whenever she said, "Irony", putting a large emphasis on the "I" and then smiling in her steely little way. If she read this book, that's what we'd be left with: Irony.
Seamus "Bok-Butler" breeds these weird goats that literally and figuratively symbolise irony. Caper Timidus has three horns (capering timidly ...) and faints inexplicably when it gets a fright. Seamus himself represents "irony" by being described as a fox (page 40 & 65) that suffers from depression, so he 'faints' at a whim too. In this way all the characters somehow have a trait similar to that of these strange animals, something that even encompasses the author of the story, who becomes part of his own tale. This alone makes the book postmodern since you're not quite sure whether it's fact or fiction. It's a fata morgana where you're supposed to laugh at the truth.