History Main / ImmortalityBeginsAtTwenty

* Inverted in ''The Meq''. The Meq attain immortality at 12 and lose it when they are ready to mate.

** ''ComicBook/WonderWoman1942'': In UsefulNotes/TheGoldenAgeOfComicBooks, the Amazons of Paradise Island were women from across history who had chosen to take an oath to uphold the Amazons' ideals and undergone training to safely drink from the Fountain of Youth, which stopped their aging. Most of the Amazons look well under thirty despite being well over a hundred, though there are a few that look older like the physician Althea.
** ''ComicBook/WonderWoman1987'': The Amazons of Themyscira have all looked like they're in their twenties since the Bronze Age as the only "new" Amazon since Aphrodite and the other goddesses created their island is Diana herself.
** ''ComicBook/TheLegendOfWonderWoman2016'': While most of the Amazons are mortals with average human lifespans those who gained imortality by becoming the champion to an Olympian like Hippolyta are all young adults in appearance despite being born in the Bronze Age.

* In the ''Literature/CommonwealthSaga'', rejuvenation, or "rejuve," treatments restore people back to their late teens/ early 20s. Most people appear to undergo rejuve when they're in their biological 50s. There's no limit on the number of rejuve treatments one can undergo, and by the time the series takes place in the 2380s, there are many individuals around [[ReallySevenHundredYearsOld born in the late-20th century.]] In the ''Literature/VoidTrilogy'', set over 1,000 years later, technology has advanced to the point where people can elect to be fitted with "biononics" that can maintain them at any biological age [[TheAgeless seemingly indefinitely]]. Most maintain themselves in their early to mid-20s, but a few keep themselves older, usually when they want to maintain an air of gravitas. For people without biononics, rejuve is still around.

* PlayedForLaughs (like just about every HighFantasy trope) in ''TabletopGame/TheSpoils.'' 3lv3s (elves) live for centuries, but spend almost all of that time as ''adolescents'', rather than young adults, meaning that the Gearsmith Trade they call home is littered with juvenile pranks and toilet humor.

-->-- ''Blog/{{Things Mr Welch Is No Longer Allowed To Do In An RPG}}'' [[http://theglen.livejournal.com/282764.html "#1616"]]

Sometimes being {{immortal|ity}} or a member of a really {{long lived}} race means that aging occurs naturally or rapidly until a character physically reaches their mid-twenties. At this point their aging stops and they get to be young and beautiful forever, or at least a very long time. Sometimes this is explained as the character being immune specifically to the degenerative effects of aging (sometimes as a side-effect of a HealingFactor) whereas ''growing'' isn't affected; other times they [[PubertySuperpower acquired their powers at a late stage of puberty]].

This is a common feature for [[OurElvesAreDifferent elves]], even if they aren't technically immortal but are just long-lived. A character that's YoungerThanTheyLook may fall under this if they weren't [[ArtificialHuman artificially created]]; sometimes a character looks like a teen or young adult but is only chronologically in the single-digits of age, maybe even BornAsAnAdult.

* [[spoiler:Vash and Knives]] from ''Manga/{{Trigun}}'' aged rapidly from birth (by the time they were a year old they were physically around 8), until they reached the physical age of men in their early twenties. Nearly a century and a half later and they haven't aged a day since.
* The Phoenix Saga of ''Manga/RanmaOneHalf'' has both versions of this. Usually the bird takes a hundred years to grow up, but if you force feed it enough it'll mature faster.
* Neo Queen Serenity of ''Franchise/SailorMoon'' stops aging at 22 (as do the rest of her supernatural friends).

* Played with in ''Manga/{{Hellsing}}''. Alucard was in his mid-forties when he died (just like the RealLife Dracula), but has the appearance of a man in his twenties [[ShapeShifterDefaultForm because he is powerful enough to assume pretty much any form he wants.]] When his full power is unlocked, he resumes his original appearance (complete with mustache), but quickly resumes his usual form (and later the form of a [[GenderBender fourteen-year old girl]]). The artificial vampirization process used by [[{{Ghostapo}} Millenium]] also restores their soldiers to a youthful state [[spoiler: most notably with Walter]].
* ''New Anime/CuteyHoney'' takes place about a hundred years after the original series, but Honey only looks a few years older . . . of course, given that she's an android, the fact that she's aged at all is surprising. Possibly justified in that she's a shapeshifter, and may have used her powers to age until her teen years were behind her.
* In ''Webcomic/HetaliaAxisPowers'' it is shown that the Nation-tans age as children, but are usually stuck at 20 or so. It shows Italy as a chibi in the age of the Holy Roman Empire, but adult by UsefulNotes/WorldWarI. It helps that a nation's age progression displays their development as countries.
* Although Witches in ''Manga/SoulEater'' live for hundreds of years, the few young witches we've seen (Angela and [[spoiler:Kim]]) are by all indications the same age as they appear to be, implying witches grow to adulthood as fast a human, then grow elderly extremely slowly. ''Manga/SoulEaterNot'' reveals this has a ''small'' degree of ProportionalAging, as [[spoiler:Kim]] turns out to be a few years OlderThanTheyLook. Presumably their aging slows down gradually instead of at an instant.

* ''Manga/YonaOfTheDawn'': When a young man drank the blood of the dragon and became the Ouryuu, he became immortal and stopped aging at 17. Since [[spoiler: Zeno]] [[ObfuscatingStupidity behaves like a goofy kid]] and kind of looks like a hobo, Yona and her companions have a hard time believing he really is the 2000 year old dragon warrior. However, since he was a skinny teenager when he became immortal and can't grow muscle, he's a poor fighter and can be easily restrained.

* Zigzagged in ''Manga/{{Bleach}}'': [[OurSpiritsAreDifferent Pluses]] appear to live much longer than humans, but how they mature and age seems to vary arbitrarily. Rukia and Renji are implied to grow from children to young adults in a roughly normal amount of time, but then don't age at all over the next fifty years. The epilogue, which takes place ten years after the series shows [[spoiler:their daughter]] who looks to be about eight or nine years old. On the other hand, Toshiro looks like he's twelve and hasn't age at all for over thirty years.
* Appears to be how aging works for half-demons in ''Anime/YashahimePrincessHalfDemon'', given that Towa and Setsuna are both teenagers and look their age, while their half-uncle Manga/{{Inuyasha}} looked no older than them when he was two hundred years old.
* ''Manga/FlyMeToTheMoon'': [[spoiler:Tsukasa has this thanks to her father forcing her to drink the immortality elixir he was meant to burn at the top of Mount Fuji on request of the Emperor (aka the real story behind the Tale of the Bamboo Cutter). As Tsukasa ''strongly'' clarifies, she isn't 1,400 years old, she's "been 16 1,400 times"]].

* The Viltrumite Nolan Grayson aka Omni-Man and his son Mark aka ComicBook/{{Invincible}} from the eponymous comic book. Mark's half-brother, Oliver, may fit this trope even more, since [[spoiler: his mother's race have exceptionally short life-spans, causing Oliver to age rapidly into a teenager in less than one Earth year, at which point his Viltrumite heritage kicks in and slows his aging process to a crawl]].
* Jenny Sparks from ''ComicBook/TheAuthority'' stopped aging at 19 and remained that way for the remainder of the 20th century. Probably applies to some of the other "century babies" too but some of them at least appear older.
* In ''ComicBook/{{Planetary}}'', main protagonist Elijah Snow is a Century Baby, human beings born at the exact moment a new century is ushered in (in Snow's case, midnight of January 1, 1900) and possess supernatural abilities, near-immortality being one of them. At the start of the series, Snow is nearly a hundred years old but appears to be in his mid-30s. While she is not a Century Baby, Planetary operative Jakita Wagner is over 60 years old yet looks no older than 30. [[spoiler: It turns out her abilities are the result of her being the daughter of a Century Baby whom Snow knew. The children of Century Babies also possess nigh-immortality in addition to various other superpowers.]]
* ComicBook/{{Wolverine}} of the ''ComicBook/XMen'' aged normally until sometime during his prime, when his aging slowed down significantly. Stories set a couple hundred years in the future often show him looking like a normal person would at 50 or 60.
* The rather obscure Comicbook/ClanDestine of Marvel has this in spades. It's not true immortality, as some of them age - just very slowly. The clan patriarch hasn't aged a day since the 12th century.
* Franchise/{{Superman}}: The comics have gone back and forth on whether Kryptonians are immortal but no matter how slowly they age in adulthood, they always age normally up to about their mid-twenties to early thirties.
* Agamemnon, leader of The Pantheon from ComicBook/TheIncredibleHulk. Although he likes appearing to people in the holographic form of a very old man with a long white beard, his immortality kicked in when he was 16. His descendants all had their immortality hit as young adults too.

* ''Franchise/WonderWoman'':
** ''ComicBook/WonderWoman1942'': In the Golden Age the Amazons of Paradise Island were women from across history who had chosen to take an oath to uphold the Amazons' ideals and undergone training to safely drink from the Fountain of Youth, which stopped their aging. Most of the Amazons look well under thirty despite being well over a hundred, though there are a few that look older like the physician Althea.

* Averted with Cosmic ComicBook/GhostRider, [[ComicBook/ThePunisher Frank Castle]] was an old man when he was dying after an attack from Thanos. Mephisto came to Frank with a deal to become the latest Spirit of Vengeance and ever since Frank was stuck as a senior citizen when he's not in Cosmic Ghost Rider form.

* ''Fanfic/ButIWroteTheWordsToTheSwanSong'': While Juliet is 13 in the [[Theatre/RomeoAndJuliet original play]], it's implied she still aged as she's [[SparedByTheAdaptation alive by the end of the play]] but eventually stopped as she has to leave Roberto and Carlotta when they begin to wonder why she isn't aging.

** This goes for most deities and immortals. Asgardians, who live to 'merely' over 5000 years old (which is suggested to be their 'three score and ten') age more or less like humans until they're about 20 or so, then stay that way for the next 2000 years - though they do steadily get more powerful. Thor and Loki are both 1500, and look like they're in their late 20s/early 30s, while their mother, Frigga, is 3500 years old and looks like a well-preserved lady in her late 50s, and their father, Odin, is between 5000 and 5500 and looks like a vigorous man in his 70s. It's also noted that they tend to age like oak trees, getting more solid and more powerful.

*** [[spoiler: Alison Carter, daughter of Peggy and Steve, looks like a well-preserved SilverVixen in her late 40s, despite being in her early 60s when the story starts. In fact, this is ''after'' she adds ageing make-up, and she actually looks about 28, at the oldest. Her children, Carol's mother Marie, and Jack O'Neill, don't have quite the same effect as the serum is less active in them, but it's implied to have slowed their ageing a little]].

** The Sorcerer/Sorceress Supreme and their designated successor tend to have a case of this, as they stop ageing once they take the position. Of course, it's also noted that the nature of the job means that the usual life expectancy is about a decade, if that. Doctor Strange is the main exception, having looked like he was in his early 40s since the 17th century [[spoiler: though in fact, it's actually the 6th century, it was caused by the Time Stone, and he's estimated that he's about 500,000 years old, thanks to a ''lot'' of time travel - and stopped counting after he hit 100,000]].
** Merlin is a literal case, being about 1500 years old and looking like 'a scruffy grad student'. He nevertheless has the gravitas to effortlessly command the respect of all around when he bothers to try - this is the only person in the entire story who can get Doctor Strange to metaphorically sit down and shut up.

* Played with in the film ''Film/InTime''. People are genetically engineered to stop aging at age 25, and continue to look the same until their time - which has become the new currency - runs out and they drop dead on the spot. At one point, Creator/VincentKartheiser's character introduces his wife, daughter and mother-in-law, all of whom look around the same age. It's also possible to kill yourself through, say, [[spoiler: alcohol poisoning]] even if you still have years left.
* In ''Film/StarTrekInsurrection'', the magic radiation produced by the planet's rings takes some time to stop/slow the aging process. So when Picard asks a young boy if he's really 75 he's told "no, I'm twelve." It also works in reverse returning people middle aged or older to their physical prime upon arriving to the planet. One of the townsfolk who looks 30ish or so mentions they were an old man when they'd first arrived, and in fact nobody in town looks older than 40 or so. Picard himself becomes notably more spry and energetic after being in the system for a while though he doesn't stay long enough to have a visable affect on his age.

* Averted in ''Film/InterviewWithTheVampire'', where "immortality" begins at whatever age you were turned into a vampire. Claudia, for instance, was bitten as a young preteen, and is ''quite'' unhappy with being stuck in a prepubescent body for hundreds of years.

* ''Literature/NightfallSeries'': Averted with Vladimir, who becomes a vampire in his thirties. Played straight with Armida and Tristan, who are both turned in their twenties.

* {{Justified|Trope}} in ''Literature/{{Kieli}}''. The [[OurZombiesAreDifferent Undying]] are immortal soldiers [[BodyHorror made out of the corpses of dead ones]]. There weren't a lot of kids fighting in the war (which doesn't mean that they weren't [[HarmfulToMinors dying in it]]), and a fully grown healthy adult is going to make a stronger, stabler, more efficient, soldier than a child. [[CameBackWrong Usually.]]

* Literature/{{Dragaera}} definitely uses this. Dragaerans are immature from about ages 1-70, but are still in fighting shape after 1,000 years. They do get old eventually, but the series is remarkably low on infirm, elderly Dragaerans, so it's not clear how long they last as "old people".[[note]]There have been a few references to some reaching 3000+, that ''look'' old-ish; most of them meet with "accidents".[[/note]]
* Played with in the third book of ''[[Literature/TheIdhunsMemories Memorias de Idhún]]''. [[spoiler: Wina, [[FertilityGod the goddess of life]], [[YouCannotGraspTheTrueForm manifest herself as a zone where all life thrives, grows and reproduces extremely quickly]]. Children become adults [[QuickAging in a matter of minutes]]. However, since the main characters are in their early twenties at this point, and the goddess of life causes growth, but not decay, they are unaffected by this. That doesn't mean they aren't [[LoveIsInTheAir affected]] by the [[ExpressDelivery "reproduces"]] part, though.]]

** ZigZaggingTrope with the elves. [[InvertedTrope Their very early development is faster than that of humans, able to walk, talk, and dance within a year.]] After that, [[AvertedTrope things slow down]], and they don't reach physical maturity until around 50 and aren't considered full adults until their first century. After that, they seem to play the trope straight, appearing young and beautiful for millennia, but they ''are'' still aging, just proportionally slowly given that their lifespans are potentially as long as ''the remaining lifespan of the universe''. The oldest elves ''do'' [[SubvertedTrope show signs of aging]], such as Círdan the Shipwright, who at the time of ''Literature/TheLordOfTheRings'' has a long white beard, which he earned by being ''over seven thousand years old'', i.e. '''''he's as old as the existence of the elvish race'''''.
** Numenoreans, at least the nobility, live two or three times as long as ordinary humans, but remain in their prime for most of it, and then will go suddenly from that to senile decrepitude in a matter of months or even weeks. At the first sign, they hand over their affairs to their children and prepare to receive the Gift of Eru (which lesser men call Death)--or at least, they were ''supposed'' to do that. When they stopped, ''that'' is when the trouble began...
** The hobbits, on the other hand, avert this: they live longer than normal humans, but also reach adulthood later (in their thirties--specifically, at thirty-three). For example, Pippin, 29, is treated like a teenager (albeit an older one--more like an 18-year-old than, say, a 15-year-old) and certainly acts as such.
* In ''Literature/PercyJacksonAndTheOlympians'' when a girl joins the hunters of Artemis, they gain immortality. Once they join they no longer age. All of the hunters are said to look in their late adolescent and teen years. Artemis says she could appear as anything she wants but [[AFormYouAreComfortableWith she prefers appearing the same age as her hunters]].
* In the ''Literature/KieshaRa'' series by Amelia Atwater-Rhodes, shapeshifters age like humans and then stop aging past 20.
%%* Played straight in ''Literature/{{Duumvirate}}'', where it's referred to as "maximum age".%%Administrivia/ZeroContextExample
* A science fiction story called ''[[http://www.benjaminrosenbaum.com/stories/start.the.clock.html Start The Clock,]]'' by Benjamin Rosenbaum, was all about the results of averting this trope. An ill-defined plague stopped everybody aging (and apparently gave immortality as a side-effect). The worst-hit group seem to be the teenagers, since their hormone overproduction ''didn't stop'', turning most into what amounts to bunch of sex-mad orcs.
* In ''Literature/TheTwilightSaga'':

** Vampires technically avert this, as humans can be turned in any age, from babies all the way to elders. Still, the vast majority of vampires in the series are young adult beauties, which invokes this trope. It isn't until ''Breaking Dawn'' that non-young adult vampires (immortal children; infant or toddler vampires) are discussed, and then only in backstory.
* The dragons in ''Literature/InheritanceCycle'' grow up within a few years, despite having very long lifespans. This is taken to the logical extreme in film, where Saphira transforms from an infant to adult in a literal second.
** Dragons reach maturity at around six months, when they're able to breathe fire, but they never stop actually growing. The largest dragons can dwarf an aircraft carrier, and they end up sleeping most of the time and living in their dreams in order to preserve their energy.
** Dragon Riders age considerably slower, but the exact details and rules around are very nebulous. Oromis lived for several hundred years and while he ''looks'' old, he doesn't have any normal signs of aging, e.g. wrinkles. Meanwhile, Brom and Galbatorix have been around for roughly the same amount of time - over a century - and lost their dragons, but Brom looks like a regular old man and Galbatorix looks to be in his 40s. Normal elves, meanwhile, also age very slowly due to their race's magical binding to dragons, and can live for hundreds, if not thousands of years without aging. The one exception might be Rhunon, but she is old even by ''their'' standards; old enough to know about life before the Riders, and bending over a forge for several thousand years can give you a bad posture.
* ''Literature/TheBelgariad''
** Sorcerers appear to be immortal. They are humans who grow up normally but, once they hit adulthood, they stop ageing. While they retain youthful vigor, Belgarath theorises that physical appearance will depend on the attitude of each individual sorcerer, who make a subconscious decision to conform their appearance to the prejudices and stereotypes of human society. As a result, because humans tend to assume old men are wise and old women are ugly crones, the male sorcerers tend to appear as old men and the female sorcerers tend to appear as young, beautiful women.
** Ce'Nedra has Dryad ancestry. She initially grows up at the same speed as a normal human so when she and Garion first meet, they are both fifteen years old. Dryads live for as long as the tree they are bonded to, so Ce'Nedra's cousins are hundreds of years old even though they look young women. Both the Gods and the Prophecy hate the inequality of love-matches where one partner is immortal and one mortal, even if they have to turn a mortal into an immortal sorcerer to ensure such equality happens. Once she reaches adulthood, it's strongly implied that Ce'Nedra will now age at the speed of a Dryad instead of a human, which is why she is destined to become the wife of the immortal sorcerer, Garion.
* Done in ''Literature/TheCompanyNovels'', where the immortals go through the immortality process from pretty much birth to age 18 and then stop aging. They have to use makeup in order to look like they are still doing so.
* ''Literature/MercyThompson'':
** All werewolves look to be in their early or mid-twenties, no matter old they were when they were turned (either continuing to mature if they were children, or reverting to the appearance of youth if they were past their prime). The only naturally born werewolf stopped aging in his mid-twenties, as well. This is stated to be part of their healing and disease resistance magic.
** Walkers, the offspring of humans and the animal spirits of North America such as [[ThoseWilyCoyotes Coyote]] can live for centuries. Mercy is only in her 20s but she has a half-brother who's also a Coyote Walker who doesn't look any older despite being something like two hundred years her senior.
* In the ''Literature/{{Deverry}}'' novels, the Westfolk age normally until they reach adulthood, stop aging for 3-4 centuries, and then age rapidly shortly before their bodies give out (so getting grey hair basically means that they have two years to live at best). Opinions are divided if the extra youth compared to humans is better than waking up one day and suddenly '''knowing''', beyond a shadow of a doubt, that someone is going to die soon.
* Played straight in ''Literature/TheGuardiansOfTimeTrilogy''. Isabel becomes ageless and stops aging at 18, just the same as her boyfriend Arkarian, who is hundreds of years old.
* In Joanna Bertin's Dragonlords trilogy, Dragonlords are humans born among humans but utterly sterile, birth marked, and with half-dragon souls; at some point these dragon souls manifest and the Dragonlord is stronger and more magical than most humans as well as able to transform into a dragon, and from that point on they age incredibly slowly. Typically they manifest in the twenties or thirties. In ''The Last Dragonlord'', the Dragonlord mentioned in the title is also called "Little One" because he's the youngest, at six hundred years old. Their leader manifested unusually young, at sixteen, and by this point is visibly old. The little one wonders about just how long she's been alive but doesn't ask.
* In J.R. Ward's ''Literature/BlackDaggerBrotherhood'' series, vampires live for hundreds of years. Their transition from "pre-trans" to full vampire occurs at about 25, and they age very slowly after that.
* Both played straight and subverted in Creator/TrudiCanavan's ''Literature/{{The Age of the Five}}'' trilogy: whilst the White and the Voices stop aging when they are 'chosen' by their respective gods, The Wilds (powerful sorcerers who develop immortality naturally) generally cease to age at the point when they discover the secret. Whilst most of the Wilds are older than twenty when this happens, due to the full emergence of their powers generally happening after [[PubertySuperpower puberty]], one of the Wilds [[spoiler: The Gull, who is the oldest surviving immortal,]] is [[ReallySevenHundredYearsOld several thousand years old]], but has the body of a child of seven or eight.
* In the ''Literature/TheWheelOfTime'' series:

* Inverted in Sean [=McMullen's=] ''Voyage of the Shadowmoon", wherein Laron is a perpetually 14-year-old vampyre. With acne and a stuck-on beard. It sucks.
* Inverted in ''The Meq''. The Meq attain immortality at 12 and lose it when they are ready to mate.
* In Kim Harrison's ''Literature/TheHollows'' it is implied that witches grow up like humans and age little for about a century after they reach their twenties, resulting in a natural life span of about 160.
* In ''Literature/HonorHarrington'', prolong recipients are "frozen" at a different age range depending on which version of the treatment they got: mid-forties for 1st, late 20s for second, and early 20s for 3rd. The freeze extends lifespan to the two to three century mark. It also has the effect of extending stages of development; Honor Harrington herself was a bit of an awkward adolescent, gangly and horse-faced, until at least well into her 30s. Such treatments are new enough during the period when most published stories are set that we don't actually get to ''see'' any characters who are 250 years old but look "only" 65 or so, but first- and second-generation recipients of the Prolong treatments do seem to get a prolonged middle age as well as the usual prolonged young adulthood.
** In "Echoes of Honor" we find out that it also extends non-visible aspects of those same periods. Honor's mother, a second-generation prolong recipient, is about 100 years old but has the body of a woman in her thirties... complete with the ability to still bear children. [[spoiler:In the wake of Honor's "death", this is exploited to resolve the issue of succession in Harrington Steading, by having her parents produce a sibling for her.]]
** This was subject to a retcon mid-way through the series. In earlier books, Prolong prolonged ''all'' stages of development, so that a bridge crewed by 20-something graduates of the naval academy looked more like a middle school class, which characters from worlds without prolong found disturbing. Later, however, it's said that children receive additional treatments so they develop up to their 20s at a more normal rate.
** JustifiedTrope: the retcon came after several mentions that crew on ships had mandatory birth control implants because, in a mixed-gender environment, sex between crewmembers would be impossible to prevent and was officially tolerated within limits. This, combined with younger crewmembers looking like very young teens or even prepubescents, raised obvious UnfortunateImplications.
* Joan of Arc in ''Literature/TheSecretsOfTheImmortalNicholasFlamel'' was turned immortal when she was a teenager, so she has this. Averted with many other immortals, though. Discussed at one point, when somebody points out that the still adolescent protagonist may want to hold off on acquiring immortality until they were at a more mature age, since otherwise they would be a child forever.
* Justified in ''Literature/DirgeForPresterJohn''. People take their third pilgrimage to the FountainOfYouth at thirty, freezing them in time at that age.
* In Creator/MikhailAkhmanov and Christopher Gilmore's novel ''Literature/CaptainFrenchOrTheQuestForParadise'', the Cell Regeneration treatment, which stops the aging process in its tracks, is performed upon request. Most people tend to do it in their early 20s, although some choose to wait until they're 30 to give themselves a more "mature" look. Since the treatment is not genetic, it doesn't affect children born of CR-treated people. The treatment is reversible, but this is only done to criminals sentenced to Aging. Interestingly, youthful looks are a moot point in the novel, as "biosculpting" has allowed people to "mold" their features to any they wish. This has resulted in worlds filled with women who look roughly the same (with main differences being hair and eye colors). The titular protagonist's choice of his next wife is partly guided by the fact that he finds a stunning beauty who doesn't look like she's been biosculpted. French himself gets weird looks from many people, since he looks to be visibly in his [=50s=] and even has some grey hairs (most people don't even know there's such a thing as grey hair). He got the CR treatment late in his life, as it didn't exist when he was born (21st century)
* In Philip Jose Farmer's ''Literature/{{Riverworld}}'', the entire human race through history over the age of 5 is resurrected on an alien planet at the same time. Everyone is at age 20, and those who were chronologically younger than 20 continue to develop until stopping at 20. There's even a term for them- "Rivertads".
* In ''Literature/JackBlank'', Revile the Undying has an age spanning millenia, but underneath his mask is only the face of a teenager. He was taken in by the Rüstov at that age and had undergone a radical reformation to transform him into a SuperSoldier that could regenerate FromASingleCell, so he hasn't changed at all in all those years.
* Played with in ''Literature/SkulduggeryPleasant'': magic is explicitly stated to be the reason for mages' long life spans but the effect it has varies from person to person, Tanith Low looks 20 but is closer to a hundred while China and the Dead Men are between three and five hundred years old and only [[DemBones Skulduggery looks his age]] but Greta Daple is 200 and looks over a hundred and complains that magic isn't consistent about how it effect the aging process. Valkyrie plays it straight as her magic is only starting to slow her aging down at sixteen.
* Played with in ''Literature/TheZombieKnight''. Reapers can stop and start their [[CameBackStrong servants']] aging pretty much as they please, limited only by how old the servant was when they died. Captain Erickson is 30 but looks and acts 10, [[CoolOldLady Octavia Redwater]] (who became a servant at 14) looks her real age of about 80, and [[LightEmUp Harper]] looks 30 but is over twice that. [[ExtraOreDinary Hector]] (currently 16) plans to wait until he's in his fifties before having Garovel stop him, [[InHarmsWay assuming he gets that old]].
-->'''Garovel:''' That’s actually a pretty common sentiment, though. You’d think more servants would want to be eternally young, but as it turns out, most sixty-year-olds don’t want strangers treating them like they’re twenty-year-olds.
* ''Literature/TheLastUnicorn'': Given his physical description, [[IneptMage Schmendrick the Magician]] was cursed with unaging immortality sometime in his twenties, or possibly even his late teens. WordOfGod puts his chronological age as anywhere between his forties and his sixties.
* In the ''Literature/ImmortalsAfterDark'' series by Kresley Cole, those born with natural immortality remain mortal until they reach the age of peak physical strength, whereupon they become fully immortal and "freeze" as they are. Then they heal perfectly from any wounds short of death, but before then, they can scar or lose body parts permanently, except for succubae, who trade on their physically flawless looks. It is unknown what happens if a human child is turned into an immortal species.
* In Creator/PeterFHamilton's ''Literature/CommonwealthSaga'', rejuvenation, or "rejuve," treatments restore people back to their late teens/ early 20s. Most people appear to undergo rejuve when they're in their biological 50s. There's no limit on the number of rejuve treatments one can undergo, and by the time the series takes place in the 2380s, there are many individuals around [[Really700YearsOld born in the late-20th century.]]
** In Hamilton's ''Literature/VoidTrilogy'', set over 1,000 years later, technology has advanced to the point where people can elect to be fitted with "biononics" that can maintain them at any biological age [[TheAgeless seemingly indefinitely]]. Most maintain themselves in their early to mid-20s, but a few keep themselves older, usually when they want to maintain an air of gravitas. For people without biononics, rejuve is still around.
* Averted in Creator/SergeyLukyanenko's ''Literature/NightWatchSeries''. The [[DifferentlyPoweredIndividual Others]] remain human until they undergo Initiation, involving their first trip into the [[AnotherDimension Twilight]], at which point they are able to tap into their magical potential. If they are of a mature age, their aging process is slowed down to a crawl. If they are children, they continue to age normally until maturity, at which point their age freezes (mostly). This applies even to [[OurVampiresAreDifferent vampire]] and [[OurWerewolvesAreDifferent werewolf]] children. Inverted in the case of [[MageSpecies witches]], who age to an "old hag" state in a mere decade, although all witches use spells to maintain a youthful appearance. This also applies to their ability to bear children. Once an Other witch is Initiated, she only has a few years to have children, before her body is no longer able to do that. There are potential Others who refuse to undergo Initiation and live out their lives normally (although both Watches agree to keep them and their loved ones perpetually healthy and off the list of vampire/werewolf hunting licenses).
* Witches and wizards in ''Literature/{{Uprooted}}'' grow to adulthood and then stop. It's mentioned that one of them, Father Ballo, spent forty years illuminating manuscripts in a monastery before someone noticed he wasn't aging. The only indication of their true age is in the eyes.
* Conrad Nomikos, the main character of ''Literature/ThisImmortal'', [[TheAgeless stopped aging]] somewhere in his mid-20s. He's looked that age for hundreds of years. He is, however, not particularly good looking. On the contrary, one of his legs is shorter than the other, he has a scarred face and heterochromia (different-coloured eyes).
* ''Literature/JourneyToChaos'': Elves stop aging once they are fully grown because their [[HealingFactor Seed of Chaos]] rejuvenates them constantly. Eric notes that Nunnal Enaz looks younger than her mortal best friend despite being older.
* This is the only drawback in Creator/DamonKnight's novella ''Dio'' (or ''The Dying Man''). In TheFuture, humans have genetically engineered themselves to [[TheAgeless immortality]] and physical perfection; a FreeLoveFuture, with [[WeWillAllFlyInTheFuture levitation]] and HealingFactor enjoyed by all. However, the way they did it was to lengthen the already long period of youth before sexual maturity, creating an asymptotic curve that never quite reaches the apex. They never mature; that's why they don't die. They 'look'' like Greek gods, but they're actually eternal kids. They're not even teenagers. This helps with population control, but they lose out on experiences only adults or the elderly can have ... except the title character, a brilliant artist whose loss of immortality is reflected in his work.
* ''Literature/MistbornTheOriginalTrilogy'': The Lord Ruler has dominated the world for a thousand years, and is worshiped as "the Sliver of Infinity" in the Final Empire. He rarely makes appearances, but when he does, people are often struck by how ''young'' he looks. He looks like a fit man in the prime of his life. [[spoiler:This is because his method of immortality involves compounding his youth to expand it infinitely. He can look whatever age he wants; he chooses to look young for obvious reasons. However, after a thousand years that age is catching up with him, so several times a week he goes to a special room in his palace where he can appear older, to give him a bit more breathing room of youth to compound.]]
* ''Literature/ANamelessWitch'' has the title protagonist cursed to be born undead. Upon turning eighteen, she stops aging and is cursed with eternal youth and beauty.
* Ann Hodgman's ''Literature/MyBabysitterIsAVampire'': Naturally-born vampires age normally until they reach a certain point, which varies depending on the individual. Vincent Graver, the titular vampire babysitter, was sixteen when he stopped aging. Subverted with his younger brother Grebiv, who stopped aging when he was just ''three''.
* Played with regarding the elves in ''Literature/{{Tinker}}'', who can live for thousands of years. On the one hand, they do stop aging physically at 'young adult', approximately their early twenties in human terms, but on the other, it takes them a century to ''get'' that far; a forty-year-old elf is physically and emotionally still a young child.
* ''Literature/NightWorld'' has a {{justified|Trope}} example with vampires. Lamia (those born as vampires) age like humans but can consciously choose to stop physically aging at any time (they can also undo this process whenever they want, which is said to have "interesting" results if you've been holding off aging for quite some time). Ash Redfern is considering stopping aging after turning eighteen, though Quinn suggests he reconsider, saying that resembling a teenager forever isn't as great as it sounds (he's been seventeen for around three centuries). The vast majority of made vampires (humans or witches transformed into vampires) resemble teens or even children, which is because most people over twenty don't survive the transformation; their adult bodies cannot adjust and they "burn out".
* In ''Literature/CarpeJugulum'', Vlad and Lachrimosa Magpyr were born as vampires. It's not entirely clear how long it took for them to become late teens, early twenties, but it's suggested they've been that way for a very long time, and will probably remain so. (Since TheMindIsAPlaythingOfTheBody works both ways on the Literature/{{Discworld}}, it's possible they'll be that way until they stop ''thinking'' like a couple of spoiled brats.)
* ''Literature/TheShadowhunterChronicles'': Warlocks age normally like humans until their early twenties, upon which they stop aging. However, their mental capacity apparently has its limits; ''Literature/TheShadowhunterCodex'' mentions a very old warlock (born before Raziel's covenant with Jonathan Shadowhunter, so over a millennium ago) who is senile, even though she presumably still looks youthful.
* ''Literature/CrestOfTheStars'' has the Abh. Barring accident or illness they live to between 200 to 250 years. From birth to 15 they age at more or less the same rate as a normal human. From 15 to 25 years their maturation slows until they're at a point somewhat equivalent to a lander at age 20 at which point they only age very, ''very'' slowly.
* ''Literature/KyoKaraMaoh'':
** While not immortal, Mazoku age ''much'' slower than humans. This is tragically {{deconstructed|Trope}} at the end of episode 47.
** Wolfram, who looks like a 15–17-year-old {{Bishonen}} physically, is actually 82.
* ''Literature/InAnotherWorldWithMySmartphone'': As Leen explains to Touya, fairies stop aging sometime between their teens and young adult years. She's an example of the former, as she's about 612 years old but looks like a pubescent girl.
* ''Literature/RedWinterTrilogy'': In the epilogue of ''Immortal Fire'', [[spoiler:Emi realizes that she has been made immortal by Amaterasu entering her body when she realizes that she hasn't aged past eighteen even though she is chronologically twenty-five]].

* ''Series/AlienNation'': In the episode "Fountain of Youth" the Tectonese (aka Newcomer) George Francisco explains to his human partner Matt Sikes that Newcomer and humans age at about the same rate until their early 20s when the [[ProportionalAging aging process slows down significantly]] for Newcomers. George goes on to explain that he and most Newcomer adults are [[OlderThanTheyLook quite a bit older]] than their appearances suggest.
* ''Series/IceFantasy'': Immortals do age beyond thirty-ish, as shown by Granny and the Ice King looking older than this, but they age very slowly and most of the immortals look roughly the same age. In some cases, like Ka Suo and his mother, parents don't look a whole lot older than their children.
* Inverted in an episode of ''Series/{{Moonlight}}'' where a vampire who was turned as a young adult has to spend the rest of his immortal life in the midst of puberty. Additionally, the original unaired pilot had the character of Josef Kostan (a 400-year-old vampire) played by the 60-something Rade Šerbedžija (to give the character some Old World wisdom) before the role was recast to the much younger Creator/JasonDohring.

** Also Claire.
** For Sylar, though, it's justified- he acquired his powers of unaging-ness when he (or the actor playing him) was in his twenties, so it makes sense that that's the age he'd stick at.
* ''Franchise/{{Stargate|Verse}}'' has this to an extent with the Ancients. While they (presumably) grow up at a normal rate compared with regular old humans, once they reach maturity they seem to be capable of staying this way for a very, very long time (millions of years if they happen to be encased in ice, as was seen in one episode... though there was limited degeneration, the Ancient in question was still perfectly able to walk, think, and understand modern humans).
* ''Series/{{Highlander}}: The Series'' both averts and explains this. Immortals are always frozen at the age when they first died, so you can get child immortals, but because immortals also tend to hunt each other down, the children don't last long, so you don't see many... the ones that survive the first few years... [[ManipulativeBastard tend to]] [[AxCrazy be off]]. Immortals above the biological age of forty also tend to be rare, for pretty much the same reason - those that aren't 'lucky' enough to start being immortal when in their physical prime (20s and 30s) are less likely to last long when other immortals come around with a sword and try to cut their heads off.
** Interestingly, the novelization of [[Film/{{Highlander}} the original film]] appears to indicate this trope originally being played even straighter, with the immortality simply kicking in at a certain age and aging stopping. However, that never made it into onscreen canon of the film. It's possible the book was created from an earlier script, before stuff had to be cut for time or whatever.
*** Actually, the film makes it apparent that Connor is already considered immortal at the time of the battle where he "died". The Kurgan was clearly trying to take his head and Connor felt The Kurgan's presence. Neither of these are possible for pre-immortals in later canon. The film also has Connor be able to survive underwater without problems. It's only later that the idea that they still die like everyone else and then come back to life is introduced.
* In ''Series/YoungDracula'', vampires age normally until they turn 16 years old. From the looks of Dracula, they probably still age a bit after that, but not much.
* ''Series/BecomingHuman'' averts this. Adam was turned at 16 and is stuck as either a schoolkid or someone in a badly-paid school-leaver job forever, since he'll never be able to pass for much older.
* ''Franchise/KamenRider'' fits this trope to the letter as later teens/early twenties is the usual age range of the lead characters.

** This also applies to [[spoiler: Kazuma Kenzaki]], who became an Undead in his early twenties. When he appears in movie special ''Kamen Sentai Gorider'' roughly 13 years later, he still looks the part. The spin-off novel brings this to its logical extreme, showing his physically unchaged, but life weary self at the age of 300.
** In ''Series/KamenRiderDouble'', Philip [[spoiler: died at age five and then was resurrected as a stream of data composed from the memories of the Earth.]] Towards the end of the show, he's confirmed to be seventeen years old, but Delusion Diary #11 hints that he won't age beyond that [[spoiler: because his body is made of data.]] It may or may not be true given that the scene was part of Shotaro's daydream.
** ''Series/KamenRiderGaim'': Played with. [[DeityOfHumanOrigin The Man of Beginning]] is still the same age as he was when he became a god. When he assumes his original form of [[spoiler: Kouta Kazuraba]], he looks the age he would be if he was still human.
* In ''[[http://nerdreactor.com/2011/10/15/curiosity-can-you-live-forever-starring-adam-savage/ Can You Live Forever?]]'' Adam finally achieves this after a long series of experimental medical procedures using MagicFromTechnology.
* ''Franchise/StarTrek''

** In the ''Series/StarTrekTheNextGeneration'' episode "[[Recap/StarTrekTheNextGenerationS3E9TheVengeanceFactor The Vengeance Factor]]" the Acamarian Yuta of Clan Tralesta was [[TheChosenOne chosen]] to carry out a mission to kill all the members of Clan Lornak no matter how long it took after the Lornak killed almost her entire clan. Among the genetic modifications made to her were ones that slowed her aging signifigantly, allowing her to spend nearly a century tracking down the last few Lornak still alive.
** This appears to be the case with Vulcans in general as well given their extended life spans. The character of Tuvok on ''Series/StarTrekVoyager'' visibly aged in appearance from the 2270s when he was a teenager to when he served on the USS ''Excelsior'' as a young adult in the 2290s. However, his appearance changed little from the 2290s up through the 2380s.
* On ''Series/TheAlmightyJohnsons'' the human reincarnations of the gods receive their powers on their 21st birthday. Olaf is the god of rebirth so he is 'reborn' each morning and thus is stuck at 21 and never ages.
* Averted in ''Series/BladeTheSeries'', where the process is different for pureblood vampires and those who were bitten. Those bitten are frozen at their current age forever (although no one appears to have been bitten as a child, so we don't know). Purebloods (those born as vampires), age extremely slowly. The pureblood who is frequently seen, Charlotte, appears to be a teenage girl but is actually around 200 years old. The mature-looking Overlord Rusk is his [=600s=]. It's not clear if the aging stops for purebloods or is extremely slow (the ''Film/{{Blade}}'' film shows an older-looking pureblood named Dragonetti).
* ''Series/TheOuterLimits1995'': In "[[Recap/TheOuterLimits1995S3E4LastSupper Last Supper]]", there's an immortal woman who actually stopped ageing at twenty. She explains that she was the last survivor of the Black Death sweeping through her village as a late teenager when she found out that she had a HealingFactor.
* ''Series/DoctorWho'': In [[Recap/DoctorWhoS35E5TheGirlWhoDied "The Girl Who Died"]], the Doctor restored a teen-aged Viking girl named Ashildr to life after she sacrificed her life to save her village. The technology the Doctor used not only saved her but rendered her functionally immortal. By the time the Doctor sees Ashildr again in [[Recap/DoctorWhoS35E6TheWomanWhoLived "The Woman Who Lived"]], she looks closer to mid-20s, but has been alive for centuries.
** Time Lords start out as children, but whenever they regenerate, their new form is adult and sometimes rather old-looking. Although each regeneration also has a very long natural lifespan in itself, so apparent age means nothing.

* Subverted in ''Series/AlteredCarbon'', set in a future where the megarich can resleeve their BodyBackupDrive in [[BodySurf another body]] when they die. Laurens Bancroft prefers to use an older body for the respect an older man commands. However his children are [[NotAllowedToGrowUp kept in young and beautiful bodies]] so Laurens can maintain his role as ThePatriarch of their family.
* Inverted in ''Series/TheMandalorian'', Mando has a bounty to retrieve an unknown target who, he is told, is 50 years old. When he finally finds his quarry, he finds an infant/toddler of Yoda's species. When he questions this to the Bounty Hunter droid IG-88, 88 reminds him that some species take longer to mature than others.
* ''Series/Ultraviolet1998''. Vampires never age past the age when they were turned. Most vampires we see were turned relatively recently, because their interactions with the mortals they've left behind are a major source of the show's drama, but there are a few striking examples including a vampire who appears to be in his 30s but is actually nearly a century old, and another who is an adult with the appearance of a child. According to the team leader, most {{Vampire Vannabe}}s are recruited when they start moving into middle age. "It's when you start realising that one day it's all going to end. No matter how many times you go to the gym."

* Religious example: Mormons (and probably other denominations believing in a physical resurrection at the Last Judgment) believe that the dead will be restored to appear as they did/would have in the prime of their lives.
** Catholics believe the same, for the blessed.
* In Hinduism, "the age of the gods is always sixteen."
* In Islam, those who enter paradise will be 33 years old eternally.

* In the Fourth Edition of ''TabletopGame/DungeonsAndDragons'', races that have lifespans greater than that of a human (for example, eladrin) follow this trope, maturing normally until around the age of twenty and staying like that for the majority of their lifespans. Previous editions gave the age at which they reached "adulthood" but no indication of the rate of maturity (which led to questions like, "is a one-hundred-and-ten-year old elf as emotionally mature as a fifteen-year old human?" and "is it wrong to bang an eighty-year old elf?")
** Quite a few sources prior to 4th have suggested that elven infants mature fast enough that elves probably aren't in diapers for twenty years, ''Webcomic/TheOrderOfTheStick'' not withstanding. It's not so much that elves take about a century to look like an adult so much as that elven culture doesn't really consider someone an "adult" until they've been living in elven society for about that long. [[Literature/TheLegendOfDrizzt Drizzt Do'Urden]] is a notable example, in that he was about 35 when he was exiled from his homeland and about 49 when he made his first appearance, yet appeared to be no younger than a teenager and no older than thirty throughout.
** Fifth edition makes this explicit. Physically they're mature at the same age as humans are, but Elven society doesn't consider them an adult until after their first century.
** Averted for half dragons (in some versions), who may not have left adolescence by the time others have died of old age. This is in line with dragon aging, where being 50 is the equivalent of the late teens and 100 is adulthood.
** Kobolds have an odd version of this. They grow and age at about ten times the speed of dragons, meaning a kobold is basically fully-grown at five and physically and emotionally mature at ten. After that, though, they age incredibly slowly, with them not being weakened by age until their sixties and not dying of old age until they're double that or beyond (and dragonwrought kobolds can make it to their 200s). This is equivalent to dragons, which only stop growing at the age of 1200. However, few kobolds actually live this long, given their status as TheGoomba; a "great wyrm" kobold is either incredibly dangerous or incredibly lucky.
* In ''TabletopGame/{{GURPS}}'' each level of Extended Lifespan doubles the amount of time spent maturing. However, Fast Maturation is available as a zero point ability with each level cutting time to mature by half causing the character to spend that much more time at their prime.
* In ''TabletopGame/{{Exalted}}'', Exalts (who may live anywhere from a few centuries to a few millenia, or even eternally depending on type) stop visibly aging until the very end of their extraordinarily long lifetimes. Since the average age of exaltation ranges from late teens to mid-thirties (there are exceptions of course. The youngest exalt was a preteen and still is after 1500ish years, while one of the oldest to exalt was over 60), they somewhat fit within this trope.

*** Solars, Lunars, and Sidereals who exalt as teenagers may follow a similar rule. The 1500 year old preteen mentioned above has spent far too much time in the Wyld and is quite messed up. The others which aren't clearly adults in the artwork are all very young and inexperienced.

* Inverted in ''TabletopGame/PrometheanTheCreated'', where ''mortality'' begins at twenty - a Promethean who completes the Great Work becomes a human in young adulthood, and can expect a normal lifespan from there on out.
* In the AD&D 2nd Edition setting ''TabletopGame/{{Birthright}}'', people can inherit divine bloodlines, which are generally assumed not to manifest until puberty. One such power is extreme long life, from five to ''one hundred'' times longer.
* The ''TabletopGame/NewWorldOfDarkness'' book ''Immortals'' features a group of beings called the Purified, who became immortal through one of several rituals that involved dying and then coming back to life. No matter how old they were when they performed the ritual, when they come back to life, they always come back in a body that is physiologically in its mid-twenties.
* ''TabletopGame/{{Warhammer 40000}}'':
** Juvenat treatments retard aging, but do not affect maturation--thus, nobles, Inquisitors, and other important people can appear to be in their thirties or forties at two to three hundred years of age. The treatments are not perfect, so the appearance of a very healthy 40-50 year old is most common, barring additional surgery.
** During the Horus Heresy the Primarchs and the Space Marines were both considered functionally immortal. The Primarchs rapidly reached maturity and then seemed to stop aging, while the process that creates the Space Marines is performed prior to puberty and bumps the subject into an eight-foot adult colossus. Post-Heresy it's a bit muddled: one Primarch is known to have survived for 1,000 years, but the rest are either dead, in suspended animation while inches from death, lost or Daemons (which immortality comes naturally for). As for the Space Marines, only one has been found to survive the 10,000 years from the Heresy to the setting's present, and he was rendered so infirm that he was unable to move and expired shortly after his discovery. The rest tend to last no longer than three centuries at war, with some reaching 1,000 years still able to fight - while there are mentions of the few Astartes who reach the millennial mark not being as spry as they were in their prime[[note]]Most notably, if Sigismund had been a century or two younger in the duel with Abaddon that kicked off the First Black Crusade, his attempt at a MutualKill would have succeeded, or possibly not have been necessary[[/note]], the simple fact that they spend 95% of their lives travelling to or in combat zones means that the fortunes of war catch up with most of them well before old age becomes a problem.
* In one of the earlier ''TabletopGame/{{Shadowrun}}'' sourcebooks, a researcher notes that elves seemed to have some kind of mechanism that caused their aging process to stop for a period of time, but there also were indicators of a latent reactivation trigger that would kick in after a couple of centuries. He then went on wondering what if there were a few that didn't have that second trigger. [[spoiler: There are a few. Harlequin is one of them. He's outlived pretty much everyone and every civilization.]]
* Played for laughs (like just about every HighFantasy trope) in ''TabletopGame/TheSpoils.'' 3lv3s (elves) live for centuries, but spend almost all of that time as ''adolescents'', rather than young adults, meaning that the Gearsmith Trade they call home is littered with juvenile pranks and toilet humor.
* A character with high Essence in ''TabletopGame/WitchCraft'' can see their aging slow to a crawl, to the point that one powerful NPC who looks to be in his mid-30's is actually over 1,300 years old. But the game specifies that Essence doesn't slow growth, just the decay caused by age. It doesn't matter how high a character's Essence is as a child, they will age normally until they reach full maturity (i.e., mid-to-late twenties).

* Raine and Genis in ''VideoGame/TalesOfSymphonia''. A bit jarring in Raine's case as she [[spoiler:looks the same age as her mother]].
** As discovered later in the game, [[spoiler:Kratos and Yuan]] both had their aging halted at twenty-something. [[spoiler:Mithos]], on the other hand, got it stopped when he was still a kid, and had to learn a special technique to make himself look older.
* The [[HalfHumanHybrid branded]] in the ninth and tenth ''Franchise/FireEmblem'' games age according to their beorc heritage until they turn [[Dangerous16thBirthday sixteen]], at which point their aging processes slow down to match their laguz heritage.
* In the ''VideoGame/{{Suikoden}}'' series; the True Runes keep their bearers from aging ''at all'', leading to one character who's been physically a child for over ''three hundred years''. The effects lasted long enough that they didn't even age while [[spoiler: the Fog Ship Guide held onto the Soul Eater]] in ''VideoGame/SuikodenIV''. Needless to say, [[spoiler: Ted's]] a bit annoyed about this.
** And apparently after taking it off, some can live for ''much'' longer due to some lingering effects of the rune, and in some cases, like with the blue moon rune, gain immortality permanently as vampires, not having to feed as long as they're in range.
** However at least the runes allow bearers to hit puberty before the whole immortality thing sets in. Otherwise characters like Luc and Sasarai who are implied to have had their runes since birth would still be infants. The theory is that the rune stops aging at its prime as defined by JRPG standard (i.e. mid to late teens).
* Pretty much how the aging process for demons native to Veldime works in ''VideoGame/{{Disgaea 2|CursedMemories}}''.
** Averted with non-Veldime demons, who typically have 500 years worth of puberty to look forward to.

* ''Franchise/TouhouProject'', especially in fanon, plays with this trope for all it's worth, thanks to its huge cast who are ReallySevenHundredYearsOld. The Scarlet sisters were born vampires and have a literal case of ImmortalImmaturity. All of the fairies in the series are referred to in ''Perfect Memento'' as having at most the appearance of a 10-year-old child and CantGrowUp. Most of the others, however, are adults who have lived thousands of years, and include some apparent teenagers who are [[CompleteImmortality truly immortal]]. Yukari, especially, (thanks to dressing up and occasionally acting like a younger woman than she appears to be normally) gets jokes from fandom about being the "old maid" (in spite of only being a couple thousand years old, which is fairly normal by ''Touhou'' standards) by some corners, and having her boast that she's (eternally) seventeen by others.
** The fairies may not fully fall under this trope as they are elemental embodiments that are reborn each time they die (which may occur with the changing of seasons according to some interpretations) rather than being immortal or long lived. The fact that the fairy maidens from the Scarlet Devil Mansion appear older then those anywhere else would suggest that fairies ''can'' age to an extent, but [[TooDumbToLive usually die]] before it occurs in any meaningful way.
** Played with another way by Byakuren, who appears to be the standard immortal hot 20-something saint. Her backstory reveals she originally hit her 80's and looked every day of it before she achieved full magical control of her body. The first thing she did was restore her own youth, the ''second'' thing she did was give herself immortality.
* After her powers manifested, Aya Brea of ''VideoGame/ParasiteEve'' actually got physically younger. While she actively refused to use her abilities between games, by the time ''VideoGame/ParasiteEve2'' rolls around, Aya is permanently 21.
* Ms. Fortune from ''VideoGame/{{Skullgirls}}'' has something like this. A stolen gem that she swallowed granted her immortality plus a wildly accelerated HealingFactor -- which explains how she survived being ''chopped to pieces'' by Dahila and her goons who tracked her down to get the gem back. She hasn't aged a day since her supposed "death", and has worked out a way to use her [[LovecraftianSuperpower newly-detachable limbs and head]] to her advantage in combat. Pity about the [[ScarsAreForever scars]], though.
* The ''Franchise/MassEffect'' plays with this repeatedly:
** Averted by the asari, who are generally thought to leave childhood at forty, and are considered mature (if rather young) adults at 80. A century-old asari is considered "barely more than a child". They give live birth and just how long gestation takes is never stated, but given a [[VideoGame/MassEffect3 conversation]] between an asari and her shorter-lived non-asari husband involving their two children, it probably is less than a decade.
** Played straight with the krogan, who are considered battle-ready at a fairly young age and ''stay'' that way for at least a thousand years. They're also explosive breeders, which is why the turians and salarians resorted to the [[DepopulationBomb genophage.]]
** Miranda states that because she was heavily genetically modified, she will likely live 50% longer than a normal human, and it is stated that her body is in its twenties even though she is in her thirties. She makes no mention of whether this affected her growth rate as a child, though [[spoiler: her genetically identical, but much younger, sister Oriana]] grew up having a normal life, which would presumably be impossible if all aging happened slower than normal, so presumably they play this trope straight.
* [[spoiler:Béluga and Elh]] from ''VideoGame/{{Solatorobo}}'' zig-zag this trope together. [[spoiler:Béluga]] plays it straight, appearing to be a young adult despite his age, but [[spoiler:Elh]] averts it by being stuck as a teenager. [[spoiler:After losing her immortality, she comments that she seems to have finally grown a bit after three hundred years.]]
* Human-passing Nobodies from ''Franchise/KingdomHearts'' can be inferred to have this. WordOfGod states they don't age, but the Nobodies who lost their hearts as kids seem to have aged normally since the time when they would have become Nobodies, while their fully-grown allies haven't aged a bit in the intervening decade-or-so (although Xaldin and Xigbar have noticeably different hair than Dilan and Braig, implying '''that''' continues to grow).
* In ''VideoGame/KingsQuestIIRomancingTheStones'' (the fan remake of ''VideoGame/KingsQuestII''), Little Red Riding Hood is retconned into a girl named Possum who lives with her elderly sick grandmother. [[spoiler: Her grandfather, in his youth, was turned into a vampire. Though he remained a friendly one, he went into seclusion, ashamed of what he had become. When he discovers that his elderly wife is about to die, he turns her into a vampire so she can live with him and be eternally young; as a result, she takes on the appearance of a 30-40 year old. He also turns Possum, previously a squeaky-voiced child, into a deep-voiced fully grown adult.]]

* In ''VideoGame/TheSims3'', supernatural Sims age normally until the Young Adult stage. After that, the lifespans of fairies and vampires are 5 times the length of regular Sims, and the lifespans of werewolves are 1.5 times as long.
** In ''VideoGame/TheSims4'', Sims that are born vampires age normally until they become young adults. Once they reach young adulthood, they stop aging entirely.
* In ''Videogame/{{Warframe}}'', the aging process of the transhuman [[PreCursors Orokin]] and their profit-crazed descendants, the Corpus, have been ''dramatically'' slowed down. Darvo is 105 years old, looks 20, and acts and is treated like an unruly teenager. However, the aging seems to stop at the mid 40s rather than 20s; Alad V, Frohd Bek, and Nef Anyo are all several hundred years old and look like 40-something [[FashionVictimVillain fashion victims]]. Teshin was around when the Orokin Empire was at its height a millenia ago and likewise looks like he's in his early 40s. [[spoiler: The Tenno look like teenagers or young adults, yet are nearly as old as Teshin. It's not made clear if it's from their life support systems, their times in cryosleep, standard Orokin augmentation, or their connection to the Void.]]

--> The typical Elm has a lifespan of roughly a millenia and a half; they age in a similar fashion to humans until the age of 20, at which point they appear 'immortal' like an elf.
* As the UltimateLifeForm, [[Franchise/SonicTheHedgehog Shadow the Hedgehog]] is completely immune to disease and his body will supposedly never age, and he's already over 50 years old. He's usually portrayed as physically the same age as the teenaged Sonic, if not a little older. The "supposedly" is due to the fact he's spent most of that 50+ years trapped in suspended animation, so it's something of an open question if he still has room to keep growing.
* Averted by Zora in ''VideoGame/TheLegendOfZeldaBreathOfTheWild''. The Zora race in the Era of the Wilds is long-lived compared to other Hyrulean races, but their growth process is appropriately elongated as well; a young-looking Zora girl notes that she's already an adult by Zora standards (and is older than most Hylian adults who visit Zora's Domain), but simply hasn't hit her growth spurt yet.

* Played straight with night elves in the ''Franchise/{{Warcraft}}'' franchise. As the ''Illidan'' novel puts it:
--> He had the ageless look of a mature night elf, which meant he could be any age from twenty years to fifteen thousand.
* ''VideoGame/{{Hades}}'': According to Eurydice, dead souls can choose which age they want to remain for the rest of eternity. Presumably, this is why Sisyphus looks middle-aged at most despite dying of old age in his myth, and why Theseus is still in his prime.

* ''Webcomic/GunnerkriggCourt'' has Jones, who has existed since [[spoiler:the Hadean eon (the formation of the Earth itself)]] and still appears to be a human woman in her late twenties or early thirties. .
* ''{{Webcomic/Homestuck}}'' gives us another long-lived example via FridgeLogic: higher-blooded trolls live much longer than lower-blooded ones with hundreds or even a thousand years difference between their expected lifespans, but all of the trolls we've seen so far appear to have aged at the same rate.

-->'''Haley''': I can't really see the downside of --\\
'''Vaarsuvius''': Twenty years in diapers.\\
'''Haley''': Oh.

* In ''Webcomic/TowerOfGod'', Rankers are people who have both climbed the tower high enough and mastered Shinsu to the point that they are completely immortal. Almost all of them look extremely young, when in fact each and everyone of them is at least ''five hundred'' years old, that being the average time it takes to become a Ranker in the first place. For example, Anaak Jahad is an extremely short and childlike [[LizardFolk lizard person]] who is in fact ''three hundred'' years old.

[[folder:Web Original]]
* Humanity in ''WebOriginal/SeventeenThousandSevenHundredSeventySix''. The entire human race mysteriously stops aging or dying ([[ImmortalInfertility or reproducing]]) in April of 2026, but it's then clarified that children conceived before that date are still born and grow to adulthood, as do those who were still children at the time.

* Most of the alicorns in WesternAnimation/MyLittlePonyFriendshipIsMagic. Justified with Twilight Sparkle, as she is seen to become one while she is young.

* The [[HalfHumanHybrid branded]] in the ninth and tenth ''Franchise/FireEmblem'' games age according to their beorc heritage until they turn [[DangerousSixteenthBirthday sixteen]], at which point their aging processes slow down to match their laguz heritage.

* In ''Webcomic/ElGoonishShive'', this holds true for elfs, the children of Immortals and humans. Adrian Raven, the son of Pandora, has been [[http://www.egscomics.com/index.php?id=2439 stuck in his early twenties for multiple lifetimes]]. The same also applies to Immortals themselves; even when they "reset" (which they need to do every couple of centuries to minimize SanitySlippage), their reset form will usually be physically and mentally a young adult. This even applies to Immortals who reset improperly, and thus do not inherit any memories from previous incarnations.

** Merlin was apparently a literal case, being about 1500 years old and looking like 'a scruffy grad student'. He nevertheless has the gravitas to effortlessly command the respect of all around.

** Wizards age much slower than normal humans, with the oldest members of the cast reaching into multiple centuries. They age normally through childhood and adolescence, with their physical aging seeming to slow down somewhere between their twenties and thirties. Old wizards do end up looking old, though a 200 year old wizard will only appear to be in their 70s.
** The extensive cast list gives way to a great number of variances of this trope. Deirdre, a roughly 1500 year old host to a fallen angel, appears to only be in her teens, while her father, one of the oldest men in existence, has the appearance of a man barely entering middle age. Some younger members of their cult, while still immortal, look to be much older physically than their leaders.

** Certain vampires, though, play this trope completely straight, and centuries-old vampires are still inhumanely beautiful.

** During the Horus Heresy the Primarchs and the Space Marines were both considered functionally immortal. The Primarchs rapidly reached maturity and then seemed to stop aging, while the process that creates the Space Marines is performed prior to puberty and bumps the subject into an eight-foot adult colossus. Post-Heresy it's a bit muddled: one Primarch is known to have survived for 1,000 years, but the rest are either dead, in suspended animation while inches from death, lost or Daemons (which immortality comes naturally for). As for the Space Marines, only one has been found to survive the 10,000 years from the Heresy to the setting's present, and he was rendered so infirm that he was unable to move and expired shortly after his discovery. The rest tend to last no longer than three centuries at war, with some reaching 1,000 years still able to fight.

* ''Series/Ultraviolet1998''. Vampires never age past the age when they were turned. Most vampires we see were turned relatively recently, because their interactions with the mortals they've left behind are a major source of the show's drama, but there are a few striking examples including a vampire who appears to be in his 30s but is actually nearly a century old, and another who is an adult with the appearance of a child. According to the team leader, most VampireVannabes are recruited when they start moving into middle age. "It's when you start realising that one day it's all going to end. No matter how many times you go to the gym."

* This is the only drawback in Damon Knight's novella ''Dio'' (or ''The Dying Man''). In TheFuture, humans have genetically engineered themselves to [[TheAgeless immortality]] and physical perfection; a FreeLoveFuture, with [[WeWillAllFlyInTheFuture levitation]] and HealingFactor enjoyed by all. However, the way they did it was to lengthen the already long period of youth before sexual maturity, creating an asymptotic curve that never quite reaches the apex. They never mature; that's why they don't die. They 'look'' like Greek gods, but they're actually eternal kids. They're not even teenagers. This helps with population control, but they lose out on experiences only adults or the elderly can have ... except the title character, a brilliant artist whose loss of immortality is reflected in his work.

* Conrad Nomikos, the main character of ''Literature/ThisImmortal'' by Creator/RogerZelazny (if the title didn't tip you off, you haven't read enough of this website) looks 23. He's looked 23 for hundreds of years.

* In ''Literature/ThisImmortal'', Conrad Nomikos [[TheAgeless stopped aging]] somewhere in his mid-20s. He is, however, not particularly good looking. On the contrary, one of his legs is shorter than the other, he has a scarred face and heterochromia (diffent-coloured eyes).