The classic example for introducing someone to kyriarchy and intersectionality is that of a white slave-owning woman. Yes, she is oppressed by the patriarchy as a system, and by individual men in particular - but it is patently ridiculous to speak of her as being oppressed by an enslaved black man given that she literally owns him.
Property by Valerie Martin is basically a novel-length exploration of these tensions, which makes for horrendous, uncomfortable reading, and teaches the reader a hell of a lot along the way.
The protagonist, Manon Gaudet, doesn't immediately come across as a villain: we first meet her observing her husband torturing a group of slaves in a bizarre sexualised ritual of his own devising. It is much later, halfway through the book, that she herself carries out a similar assault; in one of the most uncomfortable and haunting scenes I've ever read, it is made abundantly clear that she has learned nothing: her sufferings haven't made her a noble martyr. They have made her act out the abuse she's witnessed, and the abuse she's experienced, on the only person lower than her in the pecking order.
It's the slowness of the book - impressive in a not particularly hefty tome - that draws you in, allowing you to get attached to characters, to care about their sufferings, before realising, little by little, that they are ghastly people. Manon is far from the innocent victim she thinks herself to be.
The opposite is true of her antagonist, Sarah, a slave who has borne two children by Manon's husband. Viewing the world through Manon's eyes, the reader sees Sarah initially as a villain: truculent, sullen, insufficiently compliant. Rather than recognising Sarah as a fellow victim of her husband, Manon rationalises her own pain by casting Sarah as a romantic rival: a husband-stealer rather than a victim of repeated rapes. However noble we might like to think ourselves, in all honesty, this is how people tend to deal with feelings that make them uncomfortable: if there's any possible way we can go from I think I've done something wrong to THAT person, the person suffering at my hand, has done something wrong therefore I am innocent - we'll grab at it without a moment's delay.
You may have gathered that it's not the funnest book in the world. It's rare that I'll struggle through a book in which almost every character is as hideous as the cast of Property, but in this case, their faults were pretty much the point: the slow, languid reveal was compelling to the last page; the fact that I was, despite my revulsion, rooting for Manon - not to 'win' over Sarah, but to somehow build a life for herself - kept me emotionally engaged as the story rolled on to its final rotten denouement.
The major achievement of this book is that it manages to let a morally abhorrent character tell her story without endorsing it - using it as a vessel to tell the story of the slave-owning South. It notes the very real oppressions she experiences (having her inheritance pass immediately into the hands of her husband, for example) without allowing them to justify her own cruelty.
The ever-present threat of slave rebellions was fascinating from a historical perspective - the usual narrative is "black people kidnapped and enslaved, suffered voicelessly until liberated by saintly white abolitionists", so highlighting black resistance as an ongoing feature of the South was an excellent choice. It did make me want more, more of Sarah's story, more of the underground railroad. However, there is value in hearing the stories of those near the top of society - if they are told in this way. Rather than suggesting that the stories of the privileged are the only stories worth telling, novels like this point out that understanding the stories of the privileged - how they use their power, how they justify it to themselves - is vital to understanding the society they have built.