Red Oni, Blue Oni/Literature

""Most Wimseys were like the 16th Duke, and his father: 'Bluff, courageous, physically powerful' but not very intelligent; of hearty and voracious appetites of all kinds. They could be 'cruel, yet without malice or ingenuity.' The other type is physically slighter, smarter, with great nervous energy, and 'lusts no less powerful, but more dangerously controlled to a long-sighted policy.' These became churchmen, statesmen, traitors; but sometimes poets and saints."
 * Male members of the Wimsey family throughout history has turned out either Red or Blue, according to their chronicler. From the other Wiki:


 * Lord Peter, of course, is of the second type.
 * In Camus' The Stranger, the borderline-apathetic narrator Meursault is contrasted with the violent, passionate Raymond.
 * Occurs in Animorphs, where violent, aggressive Visser Three (Red) is strongly contrasted with patient, subtle Visser One (Blue)
 * The Pevensie siblings, from the movie version of Chronicles of Narnia, can be differenced by this, with Peter and Lucy represented by Red, due to the fact that they are more intuitive, vibrant, determined, and, to an extent, more sensitive than Edmund and Susan, who are more logical, cold, and down to earth, represented by Blue.
 * In Harry Potter, the Marauders' group has two sets. James Potter and Sirius Black, represented by Red, are dark-haired, rash, prankish, and Hot-Blooded. Remus Lupin and Peter Pettigrew are calmer, quieter, and more collected than them, having blue traits.
 * Wizards (dangerous fantasy) and Muggles (relatively safe reality)
 * Gryffindors (hotblooded) and Ravenclaws (intellectual)
 * Hufflepuffs (just happy to be here) and Slytherins (ruthlessly ambitious)
 * This carries over in a myriad of ways in George R.R. Martin's A Song of Ice and Fire. In addition to grandscale comparisons like the rapidly shifting seasons and entire royal families like the Targaryeans and the Starks, this dynamic also carries out between several sets of important characters:
 * Robert Baratheon and Eddard "Ned" Stark.
 * Jaime and Tyrion Lannister.
 * Arya and Sansa Stark.
 * Cersei Lannister and Catelyn Stark.
 * The Big Bad Duumvirate of The Thrawn Trilogy consists of the blue Grand Admiral Thrawn and the red Jedi Master Joruus C'baoth. Thrawn is calculating, Affably Evil, a scarily good planner, appreciates art, respects his men and his Commander Contrarian, extremely pragmatic, and has a temper, but overall is A Lighter Shade of Grey compared to, well, any of the Empire's previous leaders. Also, he has blue skin. Joruus C'baoth is domineering, believes himself to always be entirely in the right, treats non Force-Sensitives like puppets, calls the Empire his Empire, flies into a violent rage at random, constantly rejects any authority but himself, and is insane. Joruus fell to the Dark Side long ago, and the Dark Side is often represented with red. The two are often at odds and Thrawn reliably comes off looking better.
 * In Outbound Flight, the two highest-ranking people on the Trade Federation taskforce sent by Darth Sidious to destroy Outbound Flight are Kinsman Doriana and Viceroy Siv Kav. Kav is Red - he's impatient, he tries to attack Commander Thrawn's little picket force right away, he resists and blusters when Thrawn captures the two, he never learns to pronounce Thrawn's full name properly and continuously underestimates the commander, and he gets killed when he tries to kill Thrawn. Doriana is Blue and a foil, and not only does he live, he plants the seeds to Thrawn's joining the Empire.
 * It's easy to tell that Timothy Zahn likes playing the calculating type off the irrational type, and the calculating type tends to win.
 * Jack and Bob Shaftoe in Neal Stephenson's The Baroque Cycle.
 * The Dashwood sisters in Sense and Sensibility: Elinor (blue) and Marianne (red).
 * Edward Rochester and St. John Rivers. The themes of fire and water are also used to further symoblize the differences between the two.
 * Freelorn and Herewiss in Diane Duane's The Tale of Five.
 * Invoked literally in Monster Hunter Vendetta. The heroes have to defeat a pair of rampaging oni, one stronger and the other more devious, who attack a heavy metal concert.
 * In Leviathan, Sweet Polly Oliver Deryn Sharp is the red to Blue Blood Prince Alek.
 * In the Honor Harrington series, Nimitz is the Red oni to Honor's blue. He's a direct and uncomplicated soul, who is emotionally open (as befits his species), and will obliterate any enemy that comes in reach (particularly doable when you're as formidably armed as he is). Honor is the cooler, less emotionally open (though she's not emotionless) and more intellectual and nuanced member of the pair. She, true to the trope, likes water while Nimitz (being a felinoid) doesn't.
 * You also get a distinct Red/Blue flavor when Queen Elizabeth and Honor interact.
 * In The Outsiders, the difference between the greasers and the Socs is described as being that the Socs don't allow themselves to feel emotion, while the greasers feel emotions too violently.
 * Though they're both Water Masters, Peter Almsey and Peter Scott from The Serpent's Shadow definitely count.
 * From the realm of Tortall (and the Protector Of The Small series, specifically) come Nealan of Que and Keladry of Mindelan. Neal personifies the Red with his poetry, wild emotions, and inability to suffer any injustice and Kel breathes Blue with her emotionless shell and refusal to let others get to her.
 * In Death: When there's a pair of murderers, they will likely fall under this trope, like in Seduction In Death and Indulgence In Death. Would it surprise you to know that the Red Oni tends to be the weak spot of the two?
 * The Jennings series' two main characters, Jennings and Darbishire, follow this dynamic: Jennings is impulsive, brash, and extroverted (red), while Darbishire is calm, timid, and introverted (blue). The two main teachers can also be classified under this trope as Mr. Wilkins is a temperamental and emotional Jerk with a Heart of Gold (red) while admitted Author Avatar Mr. Carter is calm, reasonable, and intellectual (blue).
 * In Star of the Guardians: the passionate, proud, ambitious Derek Sagan is Red and his Star-Crossed Lover Maigrey Morianna is Blue, as she's calm, reserved, and intuitive. They even wear matching colours. Interesting that, in her youth, Maigrey was Red to her brother Platus' Blue.
 * In The Warlord of Mars, the Big Bad Duumvirate of Matai Shang and Thurid fit this. Matai Shang is blue, a cold-bloodedly arrogant Priest King of a Path of Inspiration whose primary motivation is regaining his faltering power; Thurid is a Proud Warrior Race Guy pirate lord who is primarily motivated by revenge on John Carter for publicly humiliating him.
 * The book series The Guardians of Childhood has the hotblooded ex-Cossack bandit swordsman North as red, and the intellectual martial artist Bunnymund as blue.