Granted, I may change my mind by the end of the novel ... I'm suspending judgment for now. But I'm also thinking as I read it about protagonists in fiction that readers aren't meant to like, and especially about unlikable protagonists in well-regarded fiction. One could make a long, long list; I'll content myself here with three. It's worth pointing out that I'm not talking about unlikable characters per se, and especially not about unlikable foils to likable protagonists.
The canonical character in this mold for me -- perhaps because he was one of the first and most blatant I ever encountered -- is Thomas Gradgrind, the utilitarian schoolmaster in Charles Dickens' Hard Times. The character's name is enough to have earned a callout in an earlier post, Nominative determinism in fiction, though in fact Gradgrind didn't make the cut. Here, thanks to Project Gutenberg, is how he is introduced at the start of Dickens' novel:
'Now, what I want is, Facts. Teach these boys and girls nothing but Facts. Facts alone are wanted in life. Plant nothing else, and root out everything else. You can only form the minds of reasoning animals upon Facts: nothing else will ever be of any service to them. This is the principle on which I bring up my own children, and this is the principle on which I bring up these children. Stick to Facts, sir!' The scene was a plain, bare, monotonous vault of a school-room, and the speaker's square forefinger emphasized his observations by underscoring every sentence with a line on the schoolmaster's sleeve. [...]
Not so warm & fuzzy, eh? Well, Gradgrind does come around a bit by the end of the novel, but I sure didn't like the tyrant when I met him. You have to wonder whether Roger Waters had Gradgrind in mind when he wrote Another Brick in the Wall.
That Pink Floyd classic -- which famously became an anthem for South African students rebelling against the apartheid regime (banning the song only upped the ante) -- makes for a fine segue to J.M. Coetzee's Disgrace, another Booker Prize winner, and one I count among the most elegantly rendered works of fiction in my own literary experience. Professor David Lurie is Coetzee's middle-aged protagonist, and the novel opens with his dismissal from a South African university post for having an affair with a student. He is roundly shunned, and retreats to a remote smallholding where his lesbian daughter lives. He gets in the way. Violence, rape, and Lurie's failure to find much in the way of redemption ensue. There is little to like about him, yet the book is incandescent in its portrayal of a weak man's struggle to find humanity in an unambiguously brutal world.
In Klaus Mann's Mephisto, Hendrik Höfgen trades his soul -- and throws in his politics, wife, and mistress while he's at it-- to Hermann Göring, in exchange for fame and renown as an actor in Nazi Germany. The author (Thomas Mann's son) based his story on that of his brother-in-law, Gustav Gründgens, though he denied that Höfgen portrays a particular individual. Gründgens' adopted son sued the then-publisher of Mephisto in 1968, and successfully halted its publication -- but only in West Germany. The novel was made into a film in 1981, which won an Oscar for Best Foreign Language Film. There is little to like about Höfgen either, and this is one of those rare stories that I found more powerful as a film than as a novel, but it definitely fits the "characters you're not supposed to like" rubric.
Your thoughts about unlikable characters in fiction? Personal favorites, least-liked, most outrageous? Screeds denouncing the insolence of authors who have tricked you into buying a book only to find you can't stand the company? Analysis of the fact that no unlikable character I cited in this post was written by an American?