Dolores Umbridge from Harry Potter was humiliated lots of times, then was set upon by a herd of angry centaurs, almost killed by them, suffered PTSD as a result, and later chased out of Hogwarts by Peeves the Poltergeist hitting her with McGonagall's crutch and a sock full of chalk as the students look on and cheer. She's still somewhat of a Karma Houdini when you consider that she's guilty of torture, attempted assassination, treason (after the Death Eater takeover of the Ministry), and the systematic imprisonment of innocent Muggle-Borns. If not for Word of God, we'd never have found out that she received a life sentence in Azkaban after the events of Deathly Hallows.
Happens to the two biggest villains in Animorphs. Visser One is executed via kandrona starvation, though her host is rescued, and Visser Three is sentenced to a hostless imprisonment in a special cell after being forced out of Alloran.
In book #9, The Secret, Visser Three, the Big Bad who is not afraid to deal with his adversaries in such manners as decapitation, Torture, and in one case, EATING his adversary, gets one of these. Cassie was completely surrounded by the Visser's Mooks, trapped in a box, and was still boldly claiming to be about to foil the Visser's plan. The Visser orders his mooks to surround her, and kill her. They flip the box open, ready for any number of deadly creatures to come flying out... but see nothing but a skunk in there. The Visser, not knowing what a skunk is, begins mocking her, saying "This is the best you could do?" Cue him and his mooks getting a face full of skunk juice. They run away screaming, clutching their faces. The Visser, in exchange for the "Andalite chemical technology" to get rid of the smell, agrees to let his whole plan go to pot. Ax then tells Visser Three how to get rid of skunk smell... except Ax "forgot" that you use tomato juice to get rid of it, not grape juice. A few days later, cue a very smelly, very angry, and very... purple Visser Three.
David, after spending his entire arc being a self-centered Jerk Ass. He thinks he's pulling one on Rachel but he's really being lined up for a Fate Worse than Death.
In the GONE series "King" Caine Soren gets a LITERAL conga in the fifth book when he was dragged through town half naked, hands encased in cement, a crown stapled to his head in cruel irony and is forced to dance in front of the Perdido beach Kids. Oh yeah, and he wets himself in the process. Unless he was always secretly into that kinda stuff *Wink wink*, it probably wasn't his proudest moment.
Mason Verger from Hannibal foolishly shows Hannibal Lecter how to perform auto-erotic asphyxiation. Hannibal gives him a hallucinogenic drug which Verger gratefully accepts. Hannibal is then able to hypnotise Verger into mutilating his face which Hannibal then supposedly feeds to dogs before kicking the stool from underneath Verger, breaking his neck and reducing him to a pathetic, deformed quadroplegic. Hannibal later sends Verger a letter revealing that he actually fed Verger his own face. At the end of the book, Verger's sister whom he has sexually abused, sodomises him with a cattle-prodder then rams an electric eel down his throat until he drowns in his own blood. A horrific end to be sure but a thoroughly deserved one.
The Stand by Stephen King is one long Humiliation Conga for its Big Bad, Smug Snake Randall Flagg. He has a Villainous Breakdown if so much as a spy infiltrates his territory, rapidly causing his henchmen to doubt his (supposedly) awesome power, most of which he never actually uses. His technician, the Trashcan Man, has a psychotic breakdown and blows up Flagg's nuclear weapons facility, his wife goads him into killing her (and by default, his unborn child) and his people start deserting him. Later he is mocked by one of his prisoners, loses his cool yet again and his Dragon, Lloyd Henreid, nearly turns on him. Later, after capturing the spies, he intends to mutilate them in front of his meagre band of henchmen who are now congregated in his Las Vegas Fortress of solitude. At this point, The Trashcan Man returns from the desert with an Atom Bomb and the terrified Flagg is reduced to pathetically whining at Lloyd Henreid to get rid of it. Just when it seems things can't get any worse for this absolute failure of a villain, the Hand of God (yes you heard me) appears out of nowhere and detonates the bomb. Flagg's "empire" is destroyed but he teleports away in the nick of time. He arrives on an island in the Caribbean where he begins gathering followers but ultimately dies an ignominious death in The Dark Tower series when he's eaten by a giant spider.
The Count of Monte Cristo: Edmond Dante's revenge plot is a huge Batman Gambit designed to bring this on the three men who wronged him, and it goes off pretty smoothly too. Villefort discovers that his wife is responsible for poisoning his daughter and his ex-wife's parents, for inheritance reasons (before his wife kills herself and her son on being discovered). He is publicly revealed as having attempted murder on his bastard child, said child grew up to appear in front of Villefort accused of grand larceny and fraud and reveals Villefort to his father, and to top it off his own father disinherits him. A mental and Villainous Breakdown follows. As for Danglars, his daughter runs away with her lesbian lover, he is stripped of his wealth (which is what he loves the most), and made to starve for days before being cut loose with only pocket change. And Ferdinand has his treacherous dealings published in all the tabloids, is brought to trial by the daughter of his victim, his wife and son leave him in embarassment, and in the end he eats his gun.
In Sharon Lee's and Steve Miller's Liaden Universe novel Scout's Progress, Vin Sin chel'Mara, who has made a habit of humiliating — and bankrupting — opponents at cards, is soundly defeated by a noted mathematician, who wins chel'Mara's private spaceship. When his delm learns what Vin Sin chel'Mara has been up to, he orders Vin Sin to spend a minimum of five years working on one of the family holdings, learning about soil mixtures...on a planet where gambling is illegal, to the point where being caught with a deck of cards is worth a year's hard labor, no appeal.
Happens a few times in Romance of the Three Kingdoms. Most notable are Zuo Ci's treatment of Cao Cao; Cao Cao's retreat from Chi Bi; and Meng Huo's seven defeats, with him being captured and released each time.
A protagonist example occurs in the P. G. Wodehouse story The Metropolitan Touch. To impress his girlfriend, Bingo Little gets overly ambitious in heading the production of the local Christmas play by adding in some stuff he saw in a revue in London. This in itself would have been enough to ruin him, as provincial tastes often differ from those in London. But Smug Snake Rupert Steggles pushes matters further by sabotaging the production. By the time the messy end arrives, Bingo is a pariah reviled by the locals and his girlfriend leaves him for Steggles.
In Skinny Dip by Carl Hiaasen, the second-to-last chapter has Charles Perrone hopelessly slogging through the Everglades, ruing how his former friends all turned against him, especially the ones he had tried and failed to kill. He escapes from his tormentors, only to meet for the first time the last person he'll ever see.
The Bible contains several of these, but one notable example occurs in the book of Esther. Haman, adviser to King Xerxes, has been trying to get Esther's cousin Mordecai to bow to him. Mordecai's refusal is what prompts Haman to ask the king to let him commit genocide against the Jews. In the meantime, Haman keeps looking for ways to humiliate Mordecai. One night, the king asks his scribe to read him some of the daily records as a means of helping him sleep, and it's discovered that Mordecai saved Xerxes' life once by uncovering a plot to kill him. Xerxes asks Haman what he should do to reward the man with whom he finds favor. Thinking the king is talking about him, Haman describes a grand parade through the city streets, complete with allowing the honoree to ride a royal stallion, wear a crown and have a crier go before him proclaiming, "This is what the king does for those with whom he has found favor." Thinking it's a great idea, Xerxes orders Haman to organize the parade down to the very last detail...for Mordecai. What's more, Haman himself is to be the crier, leading Mordecai around town on the king's stallion. Haman's later fate of being hanged on the gallows he built specifically for Mordecai is just the cherry on top.
Frostflower in Frostflower and Thorn suffers this, including rape, torture, public nakedness, hanging up for execution, losing her son, her powers, and her dog.
The Nome King from the Oz books goes through this. Throughout the series he is defeated by a little girl from Kansas, loses his magic belt that can grant unlimited wishes, then lays siege on Oz though unknownst to him his head general has aspirations to be The Star Scream, both of them and their entire army get splashed with a fountain that erases memories, which mentally regresses him into a infant, he gets most of his memories back except his own name yet eventually is banished from his own kingdom doomed to wander the desert for all eternity, but is soon forgiven and let back in but as the lowest ranked member of the kingdom.
Commissar Tomas Beije spends the last few chapters of The Traitor's Hand going through one of these. He grabs the chance to have Hero Of The Imperium! Ciaphas Cain arrested for desertion to find that Cain is busy trying to head off the daemon summoning that's the whole reason the Guard is on the planet in the first place. During the resulting battle, he (and his hand-picked squad, brought along to make the arrest) watch Cain go mano-a-mano with a Chaos Marine and a Daemonhost, winning both fights. In between those two encounters, he gets molested by the Slaaneshi cultist he's trying to interrogate. The board of inquiry not only completely clears Cain of any wrongdoing, but promptly files their own charges against Beiji for incompetence. Cain then coerces Beiji into an abject apology to Colonel Kasteen (who he'd insulted a few chapters ago) and assures him that he (Cain) will testify on Beiji's behalf. Finally, one member of that hand-picked squad starts a branch of the Imperial Faith that reveres Cain as the Prophet of the Emperor. note Beiji is highly fundamentalist, so having to worship the man Beiji hates would just be icing on the cake. Granted, we never find out if Beiji went back to Tallarn and encountered this sect.
Beautifully averted in John Grisham’s The Appeal. Correctly anticipating a Conga not just by the locals but by many others, Carl Trudeau makes it his personal mission to overturn a verdict against a New York City-based chemical company in which he is the main shareholder. Over the following year, the Mississippi county whose water supply was directly affected by the company’s dumping finds itself in an uphill battle to protect an appellate justice viewed as likely to uphold the verdict (and thus grant the Conga). Her replacement, recruited expressly to rule on this case, takes office a few months before it comes down. Thanks to his ruling, which breaks a deadlock, not only can the case not be re-tried or re-filed, but the remaining cases against the company have to be dropped. The final chapter sees Trudeau entertaining company on his new yacht and the company stock – now out of the town’s reach – surging.