What is the most disturbing book you've ever read and why?

There’s a pair of fantasy books by Walter Wangerin Jr, called The Book of the Dun Cow and The Book of Sorrows. Both are a mixture of Mediaeval-style beast fable and theological allegory.

The Book of the Dun Cow is sad, but also interesting and rather beautiful. But The Book of Sorrows - oh boy. The hero of the first book, the cockerel Chanticleer, has been corrupted by power and become a rapist and a brutal dictator who casually murders his own people, or orders his henchbeasats to do so. One of the main viewpoint characters, a stag, was ordered to murder a family of sapient foxes, including a baby cub, and he is slowly going mad because he can’t stop feeling the cub’s brains oozing between his hoof-claws, so he progressively beats his foot against stones until he destroys his own leg.

I was in my 30s when I read it, and I had to give up a third of the way in, because it was giving me a nervous breakdown. And Waterstone’s classed it as a children’s book because it had talking animals. When I tried to tell them it wasn’t suitable for kids they treated me as if I was some old fusspot.