These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Aurang and Aurax, twin princes of the Inchoroi. They're Serial Rapist Aliens who crash-landed during the height of the Nonmen civilization. They eventually touched off a cataclysmic war between them and the Nonmen. The Nonmen sort of started it, as they murdered the first Inchoroi captives they took. However, to bring about their victory, the Inchoroi genetically engineered three new species (the Sranc, the Bashrags, and the Wracu), the first of which is so filled with hatred and lust that the only way it can interact with its enemies is by raping them to death, killing them first and then raping them, or simply killing them in gratuitously torturous ways. Eventually, though, the power of the Quya (Nonmen sorcery) is such that the Inchoroi are driven to defeat. Aurang meekly asks the king of the Nonmen what he'd like them to do for him. He decides that he'd like his species to be immortal. The Inchoroi assent and become the physicians of the Nonnmen, wandering among them and spreading their concoctions. What happens as a result of this is completely unjustified. The men all become eternally young and immortal, but every single woman of their race dies. The remaining Nonmen are upset and decide they would like to wipe the Inchoroi out for good. Aurang and Aurax, the masterminds of the genocide, are the only survivors. But perhaps what the Inchoroi did to the Nonmen doesn't seem awful...until one realizes what it does to the surviving Nonmen. Their minds can only contain a few centuries of memory, before it starts to fade away. However, the exception to this rule is traumatic memories. Episodes of their lives filled with anguish, hatred, terror, and misery pile up, while everything beautiful and joyous, or even banal and trivial, they experience vanishes. By the time of the setting of the books, the Nonmen have been like this for at least four thousand years, and those of them that aren't trying to keep together a last remnant of their civilization are so far beyond crazy that humans can't really hope to comprehend it. And the two surviving Inchoroi don't regret a thing. This is only their backstory. In the series proper, Aurang and Aurax mastermind hundreds of horrible murders, engineer genocidal wars for their own ends, and created a being that killed every baby to be born for a decade. Both brothers are also sexual sadists who refer to themselves as 'The Race of Lovers' and are very fond of rape as an interrogation method...either doing it themselves, or letting their victims serve the srancs' pleasures.
Kelmomas, the youngest son of Kellhus. A young sociopath who murders his retarded twin brother Samarmas. Later on, he deliberately allows Inrilatas, his insane older brother, to break free from his chains in order to get him killed at Maithanet's hands. Inrilatas dies, and Maithanet himself is eventually killed at Esmenet's orders to avenge her dead son. This was planned by Kelmomas from the get-go.
Epileptic Trees: Fan theories on the nature of the No-God can sometimes veer towards this, as well as many about Kellhus.
Magnificent Bastard: Kellhus. He is biologically human, but mentally and ethically an alien without emotion. To assume control of the Holy War and make entire nations follow him, he decides to do it through religion. Kellhus slowly transforms their entire religion with himself as the Jesus Christ figure.
Seswatha's memories of the Apocalypse are literallyNightmare Fuel. The Mandate sorcerers dream it every night so they can never forget what it is they fight against. For example, Achamian once dreams of the fall of the city Sauglish. Grown men are dashing their babies' skulls against the street so the Sranc can't rape them to death and then rape the corpses. The Apocalypse is thirty-two years of Tear Jerker: Achamian virtually never refers to it without calling it "heartbreaking." Oh, and the No-God? His very existence is such that babies can't be born alive if he is. The eleven years of the No-God's existence were called "the Years of the Crib" because all babies were stillborn.
The epilogue of the second book, where the Inchoroi appear onstage, is the single most horrendous scene in this whole series, and that says a lot.
The experiments of the Dunyain upon human captives. To learn how to manipulate people by reading their facial expressions, their young are taught "neuropuncture". In this process, living captives are strapped down and their faces dissected, so teenagers can experiment with their facial muscles. While they're still conscious.
The black halls of Cil-Aujas.
The view of damnation in the afterlife that we get from Mimara's Judging Eye in The White Luck Warrior.
Shaeönanra's backstory. Also, his present physical form.
Squick: The Inchoroi are a self-described "race of lovers", wholly obsessed with sexuality, sexual violence, and rape of all sorts. And it only gets worse from there on. As a reviewer aptly put it: "Scott Bakker's books are not dark and gritty. They're pitch-black and sticky."
Some Anvils Need to Be Dropped: Kellhus corresponds to Jesus Christ. To unite mankind against the Consult, he takes control over the Holy War by intentionally reforming their religion, making them view him as a Messiah. Kellhus is tried as a heretic, hung up and left to die and then returns to life to ostensibly save everyone's souls. Oh, and he takes as his symbol the "Circumfix", which is the thing he was hung to die on.
And yet no-one knows if he's good or evil.
He's closer to an Anti-Christ . . . but this is set in a universe where such a being is probably necessary if humanity is to survive a potential Second Apocalypse.
Bakker's point in general - that people are ignorant of the cognitive biases and mental errors that condition their thoughts, and ignorant of their ignorance - might qualify as one.
Squick: These books are not for easily disturbed readers.
Incest between Emperor Xerius and his mother — especially when she gets a teenage sex slave for him, and Xerius makes his mom stay and teach the girl how to "properly pleasure" him.
A scene where the Mother-Supreme of Yatwer's cult smears blood from her period in the faces of male worshippers, "a red line of hatred", after having sex with them.
Tear Jerker: Many examples. This is probably the most depressing well-known fantasy series.
Achamian is tortured by the Scarlet Spires. His best friend Xinemus, a religious man who is conflicted about his friendship with a "blasphemer", comes to the rescue. But the Scarlet Spires subdue him and torture him as well along with Achamian, gouging out his eyes. When Achamian escapes and finally returns to the war camp, Esmenet (the woman he loves) has left him for Kellhus. The saddest part was that she had sold herself into sexual slavery to return to Achamian in the first place.
The scene where the little orphan boys watch Maithanet's procession through the streets. It's depressing because one of them prostitutes himself because he's too scared to steal, and because orphans are not considered "real children". The scene ends with that boy being taken away by a slave trader.
Cleric and his fate. Achamian was forced to kill him, because Cleric (who was insane from amnesia) loved him and Mimara to the point where he tried to kill them, in order to remember them.
Kellhus' Great Ordeal starts running into this. The Ketyai of the South, seventy thousand strong and led by King Umrapathur II of Nilnamesh, are totally annihilated by the Sranc Horde and by attacking Bashrag, while the Grandmaster of the Vokalati goes insane and starts killing both soldiers and Sranc with his sorcery. The Grandmaster of the Mandate then has to kill him, causing a battle between the Mandati and the Vokalati even while tens of thousands of soldiers are being raped to death by the Sranc below. Umrapathur dies praying that the Great Ordeal will survive him, even as the Sranc begin violating him. When Kellhus finally arrives to rescue them, the sorcerers have survived but only "scant hundreds" of the soldiers on the ground still live. Holy shit.
Uncanny Valley: Like all Nonmen, he is tall and superhumanly beautiful, with marble-white skin. But there's something very "off" about him, which all characters note. His teeth are fused, his face has the same features as a Sranc, and his voice has the "tones of a deformed child woven into it."
Unfortunate Implications: Bakker's four most prominent female characters include two whores (although one of them becomes Empress of the Three Seas, and the other is no longer a whore), a concubine/sex-slave, and a sexually predatory queen. This has led to a great deal of debate among his fans (and many who aren't) over whether this represents misogynist intent on his part.
The man himself says he/s going for mould breaking/realism: "The tendency in much fantasy fiction is to cater to readers’ moral expectations, to depict ideologically correct worlds and so avoid all the kinds of trouble I seem to get into with my fiction. In other words, the tendency is to be apologetic rather than critical (and then to be critical of those who refuse to apologize). My interest lies in the glorious ugliness that is a fact of traditional world making. Bigoted worlds. Biased worlds. Human worlds expressed through fantastic idioms."