Animorphs: Jake is melancholic (shrewd, calculating); Rachel is choleric (aggressive, driven); Tobias is supine (aloof, timid); Cassie is phlegmatic (the peacemaker); and Marco is sanguine (the cheerful jokester).
In The Armadillo with No Heart, one of these is formed when the armadillo protagonist, Kuro, joins a group of three hedgehog bandits. Kuro is fearful, shy, and lacking in self-esteem (melancholic); Morty is a kind-hearted Gentle Giant who adopts a protective attitude towards Kuro (phlegmatic); Gus is playful and childlike (sanguine), and the group leader, Clyde, is rough and abrasive (choleric).
The Bad Guys series has the five main members of "The Good Guys Club": Mr. Wolf, as the open to change leader that believes the others can become good (sanguine), Mr. Snake as the sarcastic doubter that still can't shake his evil side (choleric), Mr. Piranha as the realistic and dry member that's hiding obvious stress (melancholic), Mr. Shark as the threatening-looking, yet warm hearted and able to blend in with others (phlegmatic), and Legs, the optimistic tinkerer that doesn't let others' opinions effect him (eclectic).
In Bridge of Clay, the Dunbar brothers: Matthew is eclectic — reasonable, responsible, not prone to any outbursts; Henry sanguine — most cheerful of the family, talkative and very good at haggling; Rory choleric - hard-working (that is, once he is expelled from school and gets "real" work), rude, loves drinking and brawling; Clay melancholic — introverted, emotional, talks very little; and Tommy phlegmatic — thoughtful, sympathetic and compassionate.
Chocolate: The Consuming Passion by Sandra Boynton divides chocolate lovers into four categories, mirroring this trope: The Pastoral Chocolatist ("Pensive, pleasant, somewhat shy" — phlegmatic), the Genteel Theobromian ("Affable leader, secretly cynical" — choleric), the Refined Palate ("Artistic, intellectual, reclusive" — melancholic) and the Sensuous Chocophile ("Moody, impulsive, self-indulgent" — sanguine).
Fallon Swift and her three half-brothers in Nora Roberts's The Chronicles of The One series:
Choleric: Lord Voldemort/Tom Riddle, the power obsessed tyrant who uses his knowledge of Dark Magic to become immortal and has a volcanic temper.
Sanguine: Bellatrix Lestrange, Ax-Crazy sadist who only cares about Voldemort and the blood purity.
Melancholic: Barty Crouch Jr., the Evil Genius of the Death Eaters who managed to fool everybody including Dumbledore and was instrumental in the resurrection of Voldemort. Severus Snape would be also melancholic, being the reserved, grumpy and sarcastic teacher who is highly smart and arguably the most competent Death Eater, although he's also Dumbledore's spy and Good All Along.
Phlegmatic: Lucius Malfoy, Upper-Class Twit who has a suave if codescendent behavior to mask his loyalty to the Death Eater cause, although his deep love for his family makes him defect from the dark lord.
Eclectic: Peter Petigrew, Dirty Coward who only sides with the strong and has no real agenda of its own outside of survival.
Joni is Sanguine. She's an impulsive, charismatic and fun-loving rock singer who likes making others happy, but she doesn't always think before she acts, has some self-destructive habits and a tendency to run away from her problems until she crashes and burns. She sometimes hurts or offends people with her thoughtlessness, but never does so with malicious intent and will make amends if it's pointed out.
Helena is Choleric. She's a methodical, extroverted and practical event organiser, prone to sarcasm and bluntly honest. She can be stubborn and resentful, especially if she feels hurt or let-down, and has some issues with her sense of self-worth (especially when it comes to relationships). At the same time, she's also good at picking other people up or saying the right thing to encourage them.
Liz is Melancholic. She's a caring, hardworking and introspective GP. She is usually the most responsible and level-headed of the group, but she can sometimes come off as bossy or self-righteous to the others despite meaning well. She also tends to keep her worries and insecurities to herself, not wanting others to see her under strain but then failing to explain why she's acting a certain way.
Maggie is Phlegmatic. She's a kind, introverted and highly sensitive artist, who gets anxious easily and often doubts herself. She can be submissive with a dislike of conflict; she's easy to get along with and a great listener, but not too good at standing up for herself.
The D Squad in The Homework Machine:Kelsey (sanguine), Snik (choleric), Judy (melancholic), and Brenton (phlegmatic).
Kerri is melancholic, especially in her recurring episodes of clinical depression, although she gets better with Andy's help.
Nate is, for the most part, phlegmatic (with his Spirit Advisor hallucination of Peter giving voice to the emotions he can't let himself feel).
Peter was apparently the sanguine one among the group when he was alive, and Nate's hallucination of him still acts this way, which makes his being Driven to Suicide that much more shocking to those who didn't know him well. His Suspiciously Similar Substitute, the gang's former bully Joey Krantz, acts much the same (partly because he was never around for any of the BSDC's childhood traumas).
Rascal Does Not Dream OfBunny Girl Senpai: Snarky and calmNice Guy Sakuta is phlegmatic, note has also some minor melancholic traits at first (and kind, compassionate and quiet Shoko is phlegmatic as well especially her slightly shy young version; older Shoko mixes it with sanguine as she's more outgoing); levelheaded and witty yet kind Mai is eclecticnote at first, sort of a blend of sanguine and melancholic, as she's playful but also sensitive and sometimes pessimistic; later on, she's more of a phlegmatic-sanguine arguably; calm and rational but secretly troubled scientist Rio is melancholic, and outgoing, too much people-oriented Tomoe is sanguine. Saki Kamisato, who isn't one of the main characters, is choleric.
The Roman Mysteries: This is actually explicitly stated in the books, which is justified because it takes place during a time period when doctors still believed in the four humors.
Carmen, Tibby, Bridget, and Lena spend their first summer apart in The Sisterhood of the Traveling Pants. Carmen snaps and gets mad (choleric) so she comes home expecting Tibby to understand because Tibby walks around screaming, "Screw the world" because that's easier than feeling something (melancholic). Carmen and Tibby visit Bridget who talks about her mother and she tells her friends that she just wants to feel good and happy and alive (sanguine). The last one to join them is Lena who feels so sad that people like Kostas and Bridget who have lost everything can still be open to love while she, who has lost nothing, is not (phlegmatic).
Tywin Lannister and his brothers: Gerion, the cheery Plucky Comic Relief (sanguine). Tygett, the angry and resentful Master Swordsman (choleric). Tywin, the cold and ruthless patriarch (melancholic). Kevan, the prudent, dutiful Number Two to Tywin and the Only Sane Man (phlegmatic).
The four male Spectrums can be divided in this manner. Silas is Sanguine, being cheerful, clownish and thick-skinned, Iago is Choleric, being arrogant, ambitious and a massive chatterbox, Inigo is Melancholic, being analytical, rational and pessimistic, and Makoto is Phlegmatic, being timid, idealistic and highly ethical.
The four females can be sorted accordingly, too. Scarlett is Sanguine, being perky, flirty and fun-loving, Azurine is Choleric, being confident, hardworking and quick to anger, Minori is Melancholic, being stoic, snarky and remorseful, and Valerie is Phlegmatic, being indifferent, lazy and internally-conflicted.
