Sometimes people just fail to develop into social or intellectual maturity. Maybe it's due to a very loving but confining mother or father, who don't pressure them to get a job and move out, enabling their laziness or childishness instead. Maybe they never received any kind of proper discipline growing up, and now that they're adults, it's too late and they're set in their ways. Maybe they're a Spoiled Brat who's learned to manipulate their parents into doing what they want, and the parents have learned that it's just easier to indulge them than to fight about it. Or maybe they just didn't want to leave the nest. Maybe they've been intentionally secluded from learning about the world. Or they grew up as a neglected orphan without a proper education or any guidance towards adult life. Maybe their parents simply failed to teach them how to do things like cook for themselves, keep their home clean, balance the checkbook, make and stick to a budget, do minor home repairs, or change a tire. Maybe they were literally Raised by Wolves. Maybe it's the result of brain damage, an intellectual disability or developmental disorder, or something more sinister. Perhaps they just never had a life-changing moment involving a shotgun and a beloved pet. Maybe it's just a form of Mars-and-Venus Gender Contrast, or they live in a society with certain gender roles, where one sex is expected to be the responsible one, and the other is not expected to be (and is not always taught to be). Who can say?
Although the causes might not be clear, the effects are. The Man-Child, a term invented by William Faulkner, is usually an adult who possesses a very childlike or childish demeanor. He's emotionally both simple and fragile; he prefers (although does not always need) to have a parent figure to look after him. He usually isn't very worldly and is typically pretty gullible. The Man-Child's interests are usually what most people consider to be immature or childish, sometimes even in comparison to actual children.
The character is almost Always Male. This is (presumably) to contrast the differences between him and "normal men" with the normal responsibilities and wisdom of adulthood. The female version is usually split between The Ingenue, the Genki Girl, or other tropes which highlight an adult woman's child-like attributes rather than her grown-up persona. Manchild has many more negative connotations than The Ingenue; the manchild's immaturity and lack of outward adult behavior is emphasized as being a bad thing versus being an emphasized good thing like The Ingenue's purity and idealism. This is also because of the Double Standard most societies have, which exist for various reasons, where they expect more from men than they do from women. On the Brain Chain, the Man Child occupies a space between The Cloud Cuckoolander and The Ditz, but without necessarily becoming The Fool. He usually does not have The Fool's luck, but he doesn't necessarily play the role of the Butt-Monkey either. Although the Man-Child is commonly portrayed as being mentally challenged he does not necessarily have to be. In many cases, the character may be very intelligent, and even leave the idealism aside and be very shrewd in business or career, but this only throws him deep in the Uncanny Valley when others find out his emotional immaturity. Alternatively, his childlike qualities/way of thinking, when intelligently applied, can be a basis for his success as a businessman, in which case he's also The Wonka.
In comedic works, he usually plays the role of The Ditz. In dramatic works, he could be the Jerk with a Heart of Gold due to his simplicity or immaturity, or he could be the sympathetic character we come to love. Sometimes the Man Child embarks on a late-in-the-day Coming-of-Age Story, which ushers him into true adulthood. Note that usually Sex as Rite-of-Passage works only some of the time. In many instances, A Man Child is not necessarily a virgin, but only sees sex as a tool of pleasure and does not recognize its emotional significance. If he ever gets married, it's likely that his wife will end up being a mother-figure not only to their children but to him as well, doing all the "emotional labor" needed to keep the household afloat while he just coasts along and drags her into all sorts of wacky hijinks.
One of the Kids is related, in where their childishness is caused by spending a lot of time around children.
Does not relate to Never Grew Up, because they physically did grow up - but never outgrew being attached to immature or childish things or behavior. Sister Trope (perhaps) to Adults Dressed as Children, although that trope is almost always played for laughs or borders on the grotesque. Compare Keet, One of the Kids, Kiddie Kid. For a villainous version, see Psychopathic Manchild. Compare Basement-Dweller. Not related to Manchild, the British TV series, either. Compare and contrast The Three Faces of Adam. Contrast with Wise Beyond Their Years, where a child acts like an adult.
- Anime and Manga
- Comic Books
- Live-Action TV
- Video Games
- Web Comics
- Web Original
- Western Animation
- InSecurity has Sedine, a Cloud Cuckoolander Genki Girl who is so childish she makes Sam seem more like her babysitter than her husband, then there's Sedine's cousin Roy...
- Ted of Sally Forth (Howard) loves collecting geek memorabilia and trivia and is prone to being a Sore Loser. He's even referred to himself as such one time. There are some deconstructive elements with him, as his estranged relationship with his father is hinted to be why he regresses to childish demeanor as a coping mechanism and Sally has made it clear to him at least once that he has to become more of an adult if he wants to keep their relationship healthy.
- In Ace Combat: The Equestrian War Cloud Kicker, one of main heroines, has a very childish personality most of the time.
- A downplayed example in A Growing Affection by Naruto. Most evident when he's giddy at the prospect of building sand castles. At age 16. Painfully justifed because of Naruto's lonely and damaged childhood. After questioning him on this, Ino shuts up once Naruto reminds her of said childhood.
- In Batshark, a Fusion Fic combining a cartoon crossover with Batman, Elliot the deer plays Two-Face as a half-adult-half-manchild as opposed to a half-lawyer-half-criminal. And then there is the fusion of The Joker and The Warden...
- In Death's Design, Fate's Plan Hermione referred to Sirius as a "man child without the ability to grow up." Sirius replied that Harry's mother once said something very similar to him and Remus commented that every female he knew had said something similar at one time or another.
- Likewise, in The Life of the Legendaries, Legendaries Mew and Jirachi are extremely immature and have many, many childish habits.
- The Grand Ruler from My Brave Pony: Starfleet Magic. He likes to play hopscotch.
- In The Last Casualties Voldemort put Harry's parents into suspended animation in a pocket dimension for thirteen years instead of killing them outright. Lily called James a man child in exasperated affection when he gave Snape a "welcome back present" by turning his robe pink.
- In a bit of Fridge Logic, James and Lily were both only 21 when they would've been killed and given how Fred and George are, the comment does not have the same effect. J.K. Rowling herself admitted she actually didn't realize how young the Potters were until much later.
- In Poké Wars, Mew is depicted as being incredibly immature. As evidenced by his words upon meeting Latias.
Mew: Hi. I'm Mew. Wanna play?
- In The Power of the Mind Remus referred to Sirius as "special" while apologizing for his behavior to a Muggle salesclerk. Harry later asked if there was any truth to that because Sirius was the biggest man child he'd ever met.
- Beelzebub from Sonic X: Dark Chaos is an immature drug-fueled hedonist that would easily be the poster for a man child if he wasn't also incredibly dangerous.
- Dragon Ball Abridged portrays Nappa as this. In this story, he is a borderline disabled Psychopathic Manchild whose dialogue mainly consists of non-sequiturs and random annoyances to his partner Vegeta to the point that "Goddammit, Nappa!" has become his Catch-Phrase.
- Pacific: World War II U.S. Navy Shipgirls has Chester, who treats other peoples' weapons like toys and throws them around without second thought, not to mention acting childish even during the middle of combat.
- The Tyrant And The Hero has Black Alice, who wears a "dress that wouldnt have looked out of place on someone ten years younger" and owns a teddy bear. The plot is kicked off by her mother sending her on a journey around the world in order to gain some maturity.
- British lad-mag Loaded was predicated on this trope and serviced the needs of Man-Children who were beginning to feel marginalised and scorned by a society and culture that no longer valued them as much. At its peak in The '90s it had a circulation approavching half a million and spawned many imitators, including American equivalents like GQ and Maxim.
- Ringo Starr's persona in The Beatles. They generally gave him rather sweet, childish songs to sing, like "With a Little Help From My Friends", "Yellow Submarine", and "Octopus's Garden" (which he wrote himself).
- Blink182's "What's My Age Again?" is about a 23-year old who is about to get laid, but he gets distracted by the TV, so the girl leaves, and he prank calls her mother in retaliation.
- Buckethead, the stage persona of musician Brian Carroll, is generally built around being both childish and a little creepy. It's common for Buckethead to play with toys and trade them with the audience during his live performances. He'll also avoid talking or giving interviews in general, except in a few recorded ones where he uses his scary mask / puppet Herbie to "speak for him".
- Counting Crows' "Round Here", is about not having a conception of what being an adult means, "Round here we're never sent to bed early, no one makes us wait. Round here we stay up very, very, very, very late"
- The Idle Race's "I Like My Toys", which deals with a thirty-one year old man's desire to play with his childhood toys instead of looking for a job, much to his parents' chagrin.
- The late Michael Jackson is often said to be one, due to his building a personal amusement park in his home, Neverland Ranch (whose name also connotes this trope) and from being badly abused and denied a childhood when he was young.
- In the movie The Wall, it's implied that Old Pink is one. For example, when a girl seduces him in his hotel room, he responds by trashing up the place; in "The Thin Ice" he's seen watching a Tom and Jerry cartoon on the TV; and, in "Is There Anybody Out There?" when he's building a mandala/replica of a military barracks/whatever it's supposed to be, a battery-powered toy robot is visible among the props.
- Weezer's song "Dreamin'".
- Jonathan Richman poses as one to boast his innocent songs.
- "Manchild" by Eels from their album Beautiful Freak about his sister who committed suicide in a mental institution.
- Joni Mitchell's song "A Strange Boy" from the album Hejira is about a lover who shares some man child traits:
What a strange boy
He still lives with his family
Even the war and the navy
Could not bring him to maturity.
- Daniel Amos's "Baby Game" (from ¡Alarma!) is about a female example. It's a satire of Christians who never bother to learn anything about their faith and just keep believing exactly what they did as a child.
Little birds are helpless, way up in the tree
They cry for mother almost constantly
But little birds must one day take their wing
I told her this, she threw her rattle at me
- Alexis Laree in Bad Boys Of Wrestling. She mistook birth control for candy.
- Find an archive that houses Abyss's career (at least starting with the Abyss gimmick) and marvel as he gradually transitions from a Wrestling Monster in Puerto Rico and NWA to asking if Jacqueline on his lap means he's no longer a virgin in TNA.
- R-Truth after being betrayed by John Morrison on WWE Raw, rapidly descended into an madness and childlike behavior.
- The Rock's criticism of John Cena basically boiled down to The Rock seeing Cena as a giant child. Cena had a counter argument, though it didn't endear him anymore.
- Wrestlers who frequently throw tantrums when things don't go their way, such as Chris Jericho when he's a heel, Alicia Fox or Ken Anderson.
- Cabin Pressure gives us Arthur Shappey, the relentlessly cheerful and optimistic steward of the aeroplane who is gullible to the point of idiocy, gets ridiculously excited over Christmas, still lives with his mother, genuinely thinks it's possible for something to be bigger than the box it's in, has discovered the secret to true happiness, and thinks everything and everyone is utterly ''brilliant''. And who once killed a man.
- Willy Wonka in the 2013 musical version of Charlie and the Chocolate Factory is a downplayed version. He has a distinctly adult air of authority and elegance, but at the same time has childlike wonder, enthusiasm, impatience, creativity, and — to a lesser extent — innocence, rather Ambiguous Innocence at that.
- Batman loves the circus in Holy Musical B@man!:
Alfred: You can't stay in your pillow fort and cry forever.
- The Green Role from the Reduced Shakespeare Company's Ragtag Bunch of Misfits. Being the Man Child of the group is his defining characteristic.
- The clown in Cirque du Soleil's Saltimbanco, Eddie, is quite childlike as he pulls pranks on others and engages an audience member in a pantomimed Wild West shootout. In fact, he might actually be the adult form of the Child seen early on, if a transitional scene is anything to go by.
- Peter Pan is one in Shrek: The Musical:
Peter: Maybe if we all close our eyes and clap really hard!
Pinocchio: Oh, grow up!
Peter: I won't grow up!
Pinocchio: You're thirty-four and need a shave!
- Tobias Ragg from Sweeney Todd: The Demon Barber of Fleet Street can be played several ways, and this is one of them. Bonus points if he is still childish because of insanity and/or mental handicap, both common portrayals. The Movie made him an actual pre-pubescent boy, a method that is much harder to pull off on-stage, mostly because labor laws require underage performers to be doubled.
- The Complete History Of America Abridged depicts Ronald Reagan as an irresponsible overgrown lap-boy with an undersized puppet body who calls Nancy "Mommy."
- Fate/stay night: Saber is, we are told, not actually fifteen; after receiving her sword and becoming King Arthur, she didn't age over the next ten years, and she's really in her twenties. Not only does nobody mention how strange it is for her to have a romance with the seventeen year old main character, but she's as naive emotionally as a real seventeen year old, which is Hand Waved by claiming that as the king she had no personal life, or more specifically, she spent so much time keeping her emotions bottled away for the greater good that when put into a situation where she actually uses them leaves her vulnerable, not helped by the fact that her romance with the main character is one of the first times she legitimately felt romantic love for somebody else.
- Kyousuke from Little Busters! is a benevolent, more subtle example: because he's so obsessed with finding fun things to do, tends to be overdramatic and switch between extreme emotions, and doesn't always possess the greatest amounts of common sense (though that's not unusual in this game) he's commonly compared with a child.
- Ciel from Tsukihime has a similar situation to Saber's going on, but in that case it's actually lampshaded in Kagetsu Tohya.