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In Gone, Caine is understandably appalled at what Penny did to Cigar in the twelve hours she had him. To put it simply, she tortured him to insanity. When Lana regenerates his eyes he thinks back to some of the hallucinations she caused, and we get to see them.
In the Hive Series about a school of evil villains, villians like Dr Nero disprove of needless violence when it comes to being evil.
Tom Walker in Washington Irving's story The Devil and Tom Walker is lacking in redeeming qualities, but when he first makes his Deal with the Devil and the Devil proposes that he serve him through the slave trade, Tom immediately refuses, saying he won't have anything to do with that. He then eagerly accepts the Devil's second proposal, which is that he become a ruthless Loan Shark who ruins the lives of those around him. It's been suggested that this might have been meant satirically toward the stereotypical Northern businessman, who like Tom, was a greedy, unscrupulous miser, but abhorred slavery.
This troper was discussing this story in English class, and when the teacher brought this up, I said the name of this trope, and she said that that was very well said. Thanks, TV Tropes!
The Mallorean has a deeply chilling example in the fourth book. Belgarion finds a prophecy written by Torak, the villain of the first series. It reveals exactly what Zandramas, the current Big Bad, is planning (in essence, creating a new god of darkness). At the end, Torak has added a personal message to Belgarion... which says, in part, "If you're reading this, you've already destroyed me. What is foretold in these pages is an abomination. Do not let it come to pass." As Belgarath notes, Torak was stunned out of his madness long enough to feel revulsion at what he foresaw.
Made even more disturbing by the fact that stopping Zandramas' plan could eventually force Belgarion to kill his own young son to prevent the boy's being turned into said new god.
A less serious example is the spies within Drasnia making it a point to not spy on Queen Porenn when she's breast feeding her baby. Naturally Porenn uses this time to talk with her chief spy in total privacy by dressing him as one of her maids.
Also in his Elenium novels, after being talked into helping the newly restored Queen officialy, Platime (who was the leader of all the criminals in the country) agrees so long as he's given a full pardon, when asked for what crimes, he admits to commiting every crime except barratry and treason, and the barratry was only because he didn't know what it was.
His counterpart in Emsat, Stragen, who plays a bigger and nobler role in the sequel The Tamuli, has standards of his own. An actual bastard, he knows what it's like to be at the bottom of the social pecking order, so he trains and orders his guild to target only the nobility.
Terry Pratchett likes doing this in Discworld, especially with his Assassins' Guild. Like Leon, they do not accept contracts to "inhume" women (though they let women be Assassins, as of Men at Arms at least) or children, nor do they ever work for free, and they cannot accept contracts on someone who cannot defend himself (though "rich enough to hire bodyguards" qualifies as "capable of defending himself").
In Witches Abroad it's stated that Genua's branch of Assassins all left years ago because "some things sicken even jackals".
In Hogfather the head of the Ankh-Morpork branch is horrified by the excesses of Psychopathic Manchild Jonathan Teatime and frightened by his unpredictable actions. Teatime later hires a bunch of criminals who are also scared and repelled by him; they did kill people, but unlike Teatime, only when it was neccessary.
Fittingly for this trope, the scene that introduces Teatime notes that Lord Downey, leader of the Assassins Guild, does not have actual morals, but he does have standards. Teatime... doesn't.
In Guards! Guards!, the dragon is rather disturbed by Lupin Wonse's plan to use human psychology so that the citizens of Ankh-Morpork will begin to grow used to the idea of having to sacrifice young maidens to the dragon, and bluntly replies to Wonse that dragons "never burned and tortured and ripped one another apart and called it morality."
Moist also abhors violence (not only the violence done to him, but doing any violence himself to try to prevent it being done to him, to the extent that he absolutely refuses to carry weapons of any kind) while Gilt has no qualms about having people brutally murdered right and left and employs a particularly terrifying killer to do it for him.
It's deconstructed with Mr. Pump's speech to Moist, however, in which he points out that Moist's standards didn't stop him from ruining people's lives, kicking those who were already down and hastening their deaths anyway, even if he's not aware of it — just because what you do doesn't directly kill people doesn't mean you're not harming them, and just because other people are doing worse and more evil things than you doesn't mean that what you're doing isn't still evil.
When Mr. Pump tells Moist he has killed 2.030317 (or some such number) of people, that causes Moist to reconsider the morality of his actions.
Further to that, Vimes finds out in a later book that he's been taken off the register. Aside from being slightly disappointed at that at wondering if he can appeal, he reflects that the Assassins only take someone off the books if killing them would cause too much political chaos (Vetinari being the only other person they will not accept a contract on).
They seem to have found another use for him though, as a training exercise for over-confident students.
We also learn (in Going Postal) that Igors have a tradition and rules about making a break for it when The Marthter starts going off the deep end. You make sure the larder is full and everything is all tidy before you go, and it is, apparently, permissible (but not encouraged) to suggest that other, particularly likable servants might like to take a holiday in a different town right now. (Igors know that there's no percentage in being around when the pitchforks and torches come out.)
There's also the Thieves' Guild, which takes a very hostile attitude towards unlicensed theft. The Guild also requires thieves to stamp a receipt for the "customer", so the same people aren't hit too often or for too much.
They also strictly refrain from killing victims, although that's more to avoid trespassing on the Assassins' economic turf than for standards' sake.
In The Fifth Elephant, It's insinuated that even Serefine von Uberwald was horrified by some of the actions of her son Wolfgang, which included altering the family tradition of Hunting the Most Dangerous Game so that the human prey had no chance at survival and murdering his infant sister because she wasn't able to change form like "proper" werewolves.
Thud!! has Chrysophrase of the troll mob, who doesn't deal in drugs. Well, not any more. And not the bad drugs, the kind that kill their users or cause them to become psychotic. Commander Vimes isn't impressed. Also during that book, one of his goons makes the mistake of making an indirect threat toward Vimes's family ("He knows where I live." "Yeah, he does."). Later, Chrysophrase says the threat was not on his orders, and the offending goon has been...dealt with, and incidentally would Vimes like a rockery for his garden?
In Eric, Astfgl's attempts to run Hell like a corporation disgust even the other demons.
In The Last Hero, Evil Harry Dread has quite an extensive list of criticisms directed at modern-day villains who don't follow The Code. Yes, Harry may be a bungling Punch Clock Villain who's never rated better than a Shed of Doom, with a donkey Steed of Terror and a hamster for his Right-Hand Cat, but at least he plays his role properly.
In the James Bond book and movie On Her Majesty's Secret Service, Marc-Ange Draco, head of the Unione Corse, the biggest European crime syndicate, is an okay guy because he doesn't traffic in drugs. Murder, extortion, protection rackets, female slavery, those are fine; but drugs? No. The real Unione Corse does deal in drugs.
It's stated in Good Omens that even demons find certain actions unthinkable, including using holy water on another demon. Ironically, Noble Demon Crowley is the one who crosses that line, though it's done to save his hide more than anything else. Later on, Crowley rejects the idea of tormenting Hastur by playing the tape he's trapped on in his Bentley until he becomes a Queen song (It Makes Sense in Context) because even a demon can only sink so far.
Demons like Crowley also have this view about Satanists. Most of them (like the Sister Mary and the other nuns) are actually harmless—having been raised in the faith for generations they're like your average non-observant Christian, acting ordinary six days per week and then attending a token black sabbath without being particularly devout. Some Satanists, on the other hand, like the ones you sometimes hear about on the news...
In the Incarnations of Immortality series, Satan himself is this. While he is the absolute master of Exact Words deals, he always honors his agreements, which is much more than he can say for his recipients, who take and use the gifts then try everything they can to weasel out of the deal they made.
In IT, bully Henry Bowers and his fellow gang members just barely allow Patrick Hocksetter to hang with them, even though he fuckingterrifiesthem. Bowers eventually has enough and tells Hocksetter that he's quite well aware of the abandoned fridge that he kills animals with, which eventually leads to Hocksetter getting attacked and devoured by It.
Henry's cronies Victor Criss and "Belch" Huggins are fine with beating up smaller kids, but they are shocked when Henry tries to carve his name on Ben's stomach with a knife (though this maybe has more to do with them being afraid of getting in trouble than moral objections). Victor also has an internal monologue in which he's fine with putting fireworks in Mike's shoes, but using the powerful ones that could blow his feet off is going Too Far.
In Layer Cake, one of the gangster characters has a sex shop as a "legitimate front" and has a practice that if anyone asks for child pornography, he will arrange a covert meeting and then will beat them to within an inch of their life.
In Harry Potter, Sirius Black's evil, pureblood-maniac parents, who disowned Sirius (after he ran away) when he was sixteen, didn't join Voldemort because they thought he was going too far. Sirius's own brother, Regulus, did join Voldemort, but then when Voldemort tortures a loyal house-elf, turns against him.
Godelot Sr, writer of Magick Moste Evile, wouldn't touch the subject of Horcruxes. The notes in Tales of Beedle the Bard indicate that he was a Card-Carrying Villain.
Terry Pratchett does this again in Nation, where even cannibals revile First Mate Cox.
Sam from Villains by Necessity could be a poster child for this trope. An assassin, who is explicitly stated by the text to be an agent of Evil, Sam still refuses to kill anybody who isn't his target while on an assignment. He also refuses to steal from his targets, and hates rapists so much that they are the one exception to the above no killing rule. This is in a book where the villains are the good guys, so it all works out rather well.
In Tales of the Bounty Hunters, an anthology in the Star Wars Expanded Universe, there's a Boba Fett story. Apparently Jabba gives Leia to the bounty hunter for the night, as a reward. Fett is disgusted by this, but doesn't send her back. He gives her the bed and stands near the door, and tells her that sex before marriage is immoral and Han Solo is evil for smuggling spice—spice, in Star Wars, being anything from a drug to a rare medicine to an unusual food additive. Leia calls him out on this—one, he's a bounty hunter, essentially assassinating people for the prices on their heads, and two, he's working for Jabba the Hutt, who does a lot worse. Fett says that morality does not enter into that, because what he does is legal. Leia doesn't press it.
In Allegiance, the heroic Mara Jade does not generally get on well with Darth Vader, who always suspects her of trying to replace him. Still, she's got a much rockier relationship with the Imperial Security Bureau, saying in the narration that she knows that they are a Necessary Evil, but there's all too much evil and not enough necessary. And they do go after a stormtrooper for refusing to kill unarmed civilians; plus, they try to kill her. At the end of the book, while they're trading warnings, Mara sees that Vader doesn't like the ISB either, though probably for very different reasons.
Kirtan Loor has a couple moments like this. He's petty, puffed up, and vindictive, but when Isard talks about how the Krytos plague will decimate the Sullustans to such an extent that it might be best if they set aside some breeding stock for when the plague has run its course, Loor is taken aback and feels uneasy. The narration says that while he does consider Sullustans to be inferior, talking about them like they're grain to be poisoned for rats, with some pristine kernels held back, is a bit much. He's also sickened in General Derricote's plague lab when he sees the disease working on test subjects, and orders what he assumes to be a stricken mother and child to be taken away and cured, although he does hastily tell the General that this is part of the plan to drain the New Republic's resources. Later he becomes the leader of a terrorism front that detonates speeders filled with explosives in health centers and public places, but when his new boss orders a school to be bombed, he's horrified. His new boss sardonically mocks him. Here he is, not wanting to kill children, and yet he's performing strikes to keep people away from health centers, meaning that the Krytos Plague, which doesn't spare the young, will be less impeded.
Though Loor's reaction in the Krytos lab may have been less about standards and more an in-universe example of Nausea Fuel. Krytos is reallySquick.
Tahiri Veila chooses to offer Luke's son Ben sex in exchange for information rather than torturing him. Either option is disturbing when you consider that he's just turned 14—but, knowing 14 year old boys, is surprisingly good psychology...
According to Mara Jade in I, Jedi, Darth Sidious "would have been ashamed to use such tactics" as Mind Rape illusions.
In Bring Me the Head of Prince Charming, the demon Azzie replies to a little girl who mentions using the model guillotine he brought her on puppies:
I am evil, but I am not cruel to animals. There's a special Hell reserved for those who are.
In The Tales of Alvin Maker books by Orson Scott Card there's a quick procession of these with the latest baddies. First is the rather vile riverboat captain, who would not stoop to killing innocent (white) children. He's killed by Mike Fink, who in turn finds that he can't bear to stand and watch while their mutual employer, William Harrison, massacres a village. Finally Harrison, the worst of the three, tells Calvin that while he might be a dirty scumbag, at least he never sold his own brother out.
Although it's implied Mike only left because the hex his mother left him protected him from the curse leveled on the perpetrators of the massacre.
In Mistborn: The Original Trilogy, there are only two people Zane won't kill- Vin and his father. The former is because Vin's the one person the voices in Zane's head don't continually goad him to kill, while the latter is for no other reason than, in Zane's words, "a man shouldn't kill his father".
In the Haft Awrang book "Chain of Gold," one of the stories is that of a man who, overcome by lust, mounts a camel. This appalls even Iblis, who curses him.
In the Dale Brown novel Plan of Attack, Russian Army General Nikolai Stepashin, who sees nothing wrong with sneak nuclear bombings on North America, is disgusted by president Gryzlov's nuking of a Russian airbase to take out American infiltrators and the man's refusal to check for Russian survivors. This most likely contributes to his Redemption Equals Death later.
The Destroyer series of novels tells of the House of Sinanju, who have been assassins to the governments of the world for five thousand years. The current Master, Chiun, has been an assassin since childhood (and is over a hundred) and has perhaps half a million or so kills to his credit all done with his bare hands. But he kills child-killers and people who train children as terrorists without pay, since it's immoral to involve children in "the Games of Death".
"Gentleman" Johnny Marcone is a self-described professional monster. He directly controls all of the organized crime in Chicago and most of the police are fine with this as Marcone's desire to keep his house in order has actually resulted in crime going down since Marcone took over the mobs. He is shown to have a hand in numerous illegal and immoral enterprises... yet he draws the line at anything which exploits children and personally executes anyone he finds out has been dealing drugs to minors or pimping out children in his city.
Queen Mab, Queen of Air and Darkness. She is a cold and ruthless woman who if you injure her, she will kill you. If you betray her, she will make you beg for death. If you make a deal with her, she will keep up her end of the bargain. It may not be the nicest, cleanest means in fulfilling her end of the deal, but, like all Fae, she will honor it to the letter of the deal. It is for these reasons Harry considers her the least Evil of his options when his back is broken and his daughter will be killed soon. He could call on a Fallen Angel or some evil Necromacy ritual, but those would turn him into a truly evil monster. Mab would make him one in time, but he would only have to kill as she commanded it. And like many weapons, she wouldn't use him callously.
The more malevolent of the Fae, including the above mentioned Queen Mab, can be considered this as a whole as the Fae have a sense of morality based on deal making. Honor the deal and you do well. Break the deal or renege and you will suffer.
"When we employed the Heart of Ahriman to bring a dead man back to life," Orastes said abruptly, "we did not weigh the consequences of tampering in the black dust of the past. The fault is mine, and the sin. We thought only of our four ambitions, forgetting what ambitions this man might himself have. And we have loosed a demon upon the earth, a fiend inexplicable to common humanity. I have plumbed deep in evil, but there is a limit to which I, or any man of my race and age, can go.
The Druids of his own isle of Erin had strange dark rites of worship, but nothing like this. Dark trees shut in this grim scene, lit by a single torch. Through the branches moaned an eerie night-wind. Cormac was alone among men of a strange race and he had just seen the heart of a man ripped from his still pulsing body.
The Secret Histories series has Mr. Stab, a Jack the Ripper Expy who loves to carve up his victims. When he sees the torture the conspiracy group Manifest Destiny has inflicted on several magical beings they captured, even he is horrified.
Mr Stab: "There's only one monster here, and for once it isn't me."
Flashman is, and admits he is, evil in many ways...but even he has lines he will not willingly cross.
"A scoundrel I may be, but I ain't an assassin, and you will comb my memoirs in vain for a mention of Flashy as First Murderer." (Flashman's response to a clear hint that, if all else fails to turn him aside, Flashman is to bump off John Brown. Later, he says nearly the same thing about a proposal to have him do in Emperor Theodore of Abyssinia.)
The narrator in The Tell-Tale Heart when he refuses to kill the old man until he is awake "for it was not the old man who vexed me but his Evil Eye." (though granted his standards are insane.)
Earlier in the series, one of the senior members of Scorpia, Max Grendel, attempted to retire from the terrorist organisation, disturbed by the fact that they were developing a biological weapon that was designed to specifically target children.
In the novelization of Demolition ManSimon Phoenix is shocked that Cocteau had Associate Bob castrated to curb Bob's ambition. Phoenix is a murderous bastard, but taking a guy's balls just isn't right!
Even at his worst, Artemis Fowl II won't stand for mistreatment of the environment He also won't kill people. Lemurs, maybe, but not people. When Holly compares Artemis to the villain Jon Spiro, Artemis uses this fact as his defense.
In Gilded Latten Bones, Garrett ponders this trope when he asks Sarge and Puddle, two of assassin-for-hire Morley Dotes's criminal associates, about the doings of TunFaire's resurrection men, and both are repulsed by the notion of stealing dead bodies for necromantic research.
In Warrior Cats, there is one villain called Mapleshade who is so screwed up all the other villains are scared of her.
In The Pool of Fire Will is horrified by a German town in which criminals are given to the Tripods to be hunted for the crowd's amusement. He notes that in England executions are regarded as an unpleasant chore, not a sport.
In in the Gor series rape and slavery are fine. On the other hand raising a girl from infancy with no concept of the outside world, sexuality, violence, or even men and then raping her is still viewed as horrific. That it drives the girls insane and they have to be killed the next day is probably a contributing factor.
In the novel In Enemy Hands, Citizen Captain Vladovich is so vicious he is unpopular even with other State Sec members.
Likewise, in Honor Among Enemies, even the crew of the PNSVaubon is disgusted by theacts of Andrew Warnecke's pirates.
In the BattleTech novel 'Star Lord,' it's implied that there's rogue mercenary and pirate bands who turned down offers to work with an otherwise charismatic and surprisingly well heeled leader not unlike a Bandit King when they discovered he was a direct genetic descendant of the setting's greatest and most infamous monster looking to finish what his ancestor started. These pirates are generally taking slaves, burning villages, and otherwise being barbaric...and they still don't want to be associated with this guy. Some groups eventually did join his army, in a flat aversion of this trope.
In Death: An example of this occurred in Betrayal In Death. There was a trio of thieves named Naples, Gerade, and Hinrick. However, when Hinrick found out that Naples planned to have people working for Roarke murdered, he pulled out, greatly enraging Naples. Hinrick doesn't deal in murder, because he considers it rude.
Sven Hassel writes of soldiers in a penal battalion, some of the roughest, cruelest, most degraded men in the forces of Nazi Germany...but sometimes they run across things done by the Nazis, or the Soviets, that repulse even these hardened, callous killers. When they get a chance to express their disapproval of such things in concrete form, it can get...messy.
Vince in Watchers is a ruthless killer, but he's also a rather considerate guy who has a code of honor and a clear sense of empathy for others. However, he is Ax-Crazy and his code is based on Blue and Orange Morality, so it really doesn't make him any less evil or any less terrifying.
Three witches from Christopher Moore's Fool admit being evil incarnate but they say to preffer staying away from politics - apparently even crushing toddler's skull is better than it.
Simon Heap, when he has shoot down Nicko with a ThunderFlash:
Don't worry, I don't harm family.
In Darke, Linda decides to invoke You Said You Would Let Them Go on a pair of lovebirds after holding one hostage to make the other bring Jenna to her. The Witch Mother stops her because a witch must keep her Darke bargains, and Linda seems to be forgetting the Rules.
In The Hunger Games, residents of the Capitol have no problem with watching children as young as twelve murder each other for entertainment. But when Peeta "reveals" that Katniss is pregnant, they go ballistic.
Also, while they are known to demand sexual favors from the winners (one of many downsides if you're a winner who's on the attractive side) doing so if he or she is underage crosses the line (at least they say that publically). In the first book, it was explained that after Finnick won at fourteen, "they couldn't really touch him for the first year or two. But ever since he turned sixteen..."
Lord Tywin Lannister of Casterly Rock will not shy away from monstrous acts, but he does them according to an ice cold calculation of benefits and he prefers them carried with equally cold blooded efficiency. He reacts with disgust to the murder of the young Princess Rhaenys not because a young girl was murdered, but because his brutal Mook Lieutenant who did it stabbed her something like 50 times when, as Tywin puts it "Anyone with the wits the gods gave a turnip would have spoken some soothing words to her and then smothered her with a pillow."(For context, Princess Rhaenys was a girl who was maybe 5 years old and had been found hiding under her father's bed while the capital was being sacked.)
The Guild of the Faceless Men will only kill their targets, not bystanders or even bodyguards.
The Ironborn hate slavery, although they have a very flimsy definition of it. Indentured servitude and forced prostitution: okay for them, but buying and selling people? NEVER!
While both are terrible, there are in fact differences: thralls can have kids who are not only free but full citizens. Slaves can't. In addition, thralls are taken in combat, which a Proud Warrior Race culture would value, whereas any weakling with money can buy a slave.
Ser Jaime Lannister is, at least in the early part of the series, a pretty nasty fellow, but he was still known for this trope enough that the Starks ruled him out of the attempted assassination of Jon Arryn because it was felt Ser Jaime would look down on the use of poison.
Well, it's partly this and partly that he's impulsive and easily bored. Poison isn't really his style. He'd be more likely to just go out and stab the guy and figure out the unimportant details later (or, I suspect, get Tyrion to figure them out for him).
He is also disgusted by Gregor Clegane's wanton sadism and the Red Wedding.
Ser Bronn of the Blackwaterwould hurt a child. He'd want a decent price for it, though.
In the Vorkosigan Saga, one of the main industries of Jackson's Hole is making clone-slaves; including clones that allow rich men to achieve immortality by transplanting their brains and throwing away the old one, thus killing it's personality. Nearly everyone outlaws that. On Jackson's Whole there isn't any law.
In the Belisarius Series, Narses practically lives this trope. He betrayed Empress Theodora who was practically his adopted daughter. But when told to assassinate the family of a Rajput chief, he refuses and almost becomes a hero.
In Gene Stratton Porter's Freckles, Black Jack has agreed that Wessner can kill Freckles, however he likes, once they are gone, but he objects to watches while Wessner torments him, especially since Freckles would beat him in a fair fight. Another man is angry that Wessner didn't just keep Freckles from seeing any of them.
"You see here, Dutchy," he bawled, "mebby you think you'll wash his face with that, but you won't. A contract's a contract. We agreed to take out these trees and leave him for you to dispose of whatever way you please, provided you shut him up eternally on this deal. But I'll not see a tied man tormented by a fellow that he can lick up the ground with, loose, and that's flat. It raises my gorge to think what he'll get when we're gone, but you needn't think you're free to begin before. Don't you lay a hand on him while I'm here! What do you say, boys?" "I say yes," growled one of McLean's latest deserters. "What's more, we're a pack of fools to risk the dirty work of silencing him. You had him face down and you on his back; why the hell didn't you cover his head and roll him into the bushes until we were gone? When I went into this, I didn't understand that he was to see all of us and that there was murder on the ticket. I'm not up to it. I don't mind lifting trees we came for, but I'm cursed if I want blood on my hands."
Parodied in the Ciaphas Cain novel Duty Calls. Cain considers the uniforms of the PDF so garish that even Slaaneshicultists would find them distasteful.
This trope appears in Israeli poet Natan Alterman’sSummer Celebration, Miriam Helen asks notorious robber Misha Barkhasid to help her fight off Woldarski, the man she eloped with who threatened to ruin her face with acid if she doesn’t work as a prostitute for him. Barkhasid says that a man of honour can live on robbery, but not ‘will never live on the profits of a woman’s body’.
In the Star Trek: The Next Generation novel Imzadi, the Sindareen leader of a raid on Betazed has no qualms about theft, violence and killing if necessary but his captive Deanna Troi's empathic abilities tell her he won't rape her.
Troi : "You're not a rapist. A thief, yes. A killer as needed. But not a rapist."
In Valor's Trial by Tanya Huff, the Others hit the ground battle from space with some sort of strategic warhead that fuses the entire battlefield and everything on it into smooth volcanic glass. According to an Other lieutenant that Torin Kerr teams up with later on, at least part of the Others' own ruling council considered this weapon horrific and tried to prevent its use.
Rainbow Six: Dimitriy Popov is an ex-KGB agent contacted by the bad guys to foment terrorism in Europe, which he does with enthusiasm for a rather large paycheck. The bad guys, who are planning human genocide on a planetary scale with only a handful of select survivors, eventually decide to let him in on their plan and include him in the chosen elite. He's so horrified by their plan that he runs away and rats them out at the first chance he gets. His information is instrumental in stopping them, effectively saving humanity.
In the first Gentleman Bastard book, we find Locke Lamora risking his life, his treasured vengeance—-and he's a vengeful sort from a vengeful people and his freedom to warn his enemies about something that he thinks is just plain wrong. And The Thiefmaker is perfectly willing to kill children—-but he always makes the correct offering to the gods for the murder, and absolutely won't sell a child to slavers for any amount of gold.
The Thiefmaker's attitude may partly be Pragmatic Villainy; being The Fagin is tolerated, but dealing with slavers is not, and the authorities are generally very serious about that.
And in the second book, Red Seas Under Red Skies, he goes out of his way to trash and rob Salon Corbeau, a city dedicated to letting the decadent rich do as they please, because he's disgusted by one of their pastimes.
Jake: He's a prisoner of war. We don't kill prisoners.
The Visser: No. Of course not. You merely blow up ground-based Yeerk pools and kill thousands. And then another seventeen thousand of our brothers here on this ship. Defenseless, harmless, unhosted Yeerks. Murdered. But you don't kill prisoners.
Damon Runyon's characters are generally pretty blase about crime, but there are things they would never, ever do. In the story "Gentlemen, the King!" three New York City hardboys recruited to kill a king in Europe abort the mission instantly when they find out that the King in question is a child... and end up killing the man who sent them, instead.
In The Lord of the Rings, orcs are Always Chaotic Evil servants of the Dark Lord who routinely kill and eat civilians, and are constantly waging war against each other. "Kindness" is a dirty word to them, and they torture people for fun. But eating other orcs is one thing they won't tolerate.
Technically, they hate being accused of cannibalism. Whether or not they actually practice it is unclear.
(Jim) Rawlings was a burglar and a thief, but like much of the London underworld he would not have anyone "trash" his country. It is a fact that convicted traitors in prison, along with child molesters, have to be kept in seclusion because professional "faces", if left alone with such a man, are likely to rearrange his component parts.
Older Than Steam: In Dr Faustus the freaking demon Mephistopheles tries to convince Dr Faustus that selling your soul for magic power is a bad idea. Several times, actually. He explicitly points out that a few years of screwing around with physics isn't worth the loss of eternity with God.
In the novel The House of Silk (the new Sherlock Holmes novel by Anthony Horowitz) we learn that even the Napoleon of Crime himself (never named in the book but it's obviously him) has standards he finds the child sexual abuse practice in the eponymous house so appalling he gives Watson information which directly assists in solving the case. The section where this happens is very well-written and despite this moment of dog-petting the reader is left in no doubt that Moriarty is a very sinister man indeed.
In The Box of Delights, Abner's henchman Joe objects to keeping clergymen and choirboys prisoner at Christmas, partly because he hopes it would "tell in our favour, if ever we come to be tried", but also because it's "not Christmas dealing".
In the Humanx Commonwealth novel Bloodhype, the AAnn commander on Repler is a proud member of a xenophobic imperial race that would cheerfully eat humans for dinner were it not against the terms of their treaty, but even he is appalled when confronted with Dominic Rose, a drug lord (and distributor of the eponymous narcotic) who would gladly sell out his own species for survival.
In A Clockwork Orange, the gangs may be brutal rapists and robbers, but they have a strict prohibition on having more than five members in each gang; Billy Boy has six, which is the main reason Alex holds him in such low regard. Also, it’s implied they completely refuse to kill anyone; at any rate, Alex is horrified when he learns he accidentally killed the old woman he robbed.