Semi-Immortality

Semi-Immortality
Galadriel (The Lord of the Rings), like other Elves of Middle-earth, cannot age, but can be slain or die of grief.
Power/Ability to:	Not age.

"Fifty years have passed... but I do not age. Time has lost its effect on me."

― Jack (Samurai Jack)

"Not bad for a seven hundred years old."

― Sabra/Ruth Bat-Seraph on Gabriel Shepherd (Marvel Comics)

"So you're having a midlife crisis."

"Well...I'm extremely old. I think I'm entitled."

― Dean Winchester and Castiel (Supernatural S10E9: The Things We Left Behind)

"Ah, Sanderson. The decades have treated you well. All grim and grown, are we? No longer Wesley Dodds' Golden Boy, I see."

― Johnny Sorrow to Sanderson Hawkins (DC Comics)

The power to not age. Absolute form of Longevity. Lesser version of Immortality. Opposite to Immortal Aging.

Also Called

• Absolute Longevity
• Age Anchoring/Locking
• Ageless Longevity
• Agelessness
• Aging Immunity
• Biological Immortality
• Eternal Youth
• Fixed/Locked Age/Youth
• Half-Immortality
• Limitless/Prolonged Lifespan
• Perpetual Lifespan/ Youth
• Self-Age/Aging Negation
• Senescence Immunity
• Timeless/Unaging Body
• Virtual-Immortality

Capabilities

Users of this ability never age, and as a result, they stay young forever or at least never suffer the ravages of aging. Because of this, the user will always be at their physical prime. The user will also be immune to aging abilities, such as Age Acceleration or Reversal.

Applications

• Immunity to age-based powers.
• Prime Form (permanently)

Associations

• Age Deceleration
• Age Manipulation
• Age Negation
• Artificial Physiology
• Bionic Physiology
• Contaminant Immunity
• Decelerated Aging
• Enhanced Condition
• Immortality
• Life Extension
• Multiple Lives
• Old Prime
• Redundant Physiology
• Regenerative Healing Factor
• Self-Sustenence
• Superior Human Physiology
  • Prime Superior Human Physiology
• Telomere Regeneration
• Temporal Immunity
• Temporal Lock
• Youth Embodiment

Limitations

• User is still vulnerable to everything else that would affect other beings, from disease to mortal wounds.
• Users may stop aging only after they reach a certain point.
  • Depending on what that point is, the user may never reach adulthood.
• Still does not prevent against Life Reduction.
• The user may be suffered from grief as they may watch other people meet the end of their lives which can cause severe psychological effects on the user.

Trivia

• Unlike other forms of Immortality, this version is really hard to detect whenever it comes to physiological science. To basically put it, users of this power are still mortal, but except their bodies don't age at all, making this form of immortality half-baked in terms of functionality.

Known Users

See Also: The Ageless.

Anime/Manga

• Suzu Shutō (Akuma no Riddle); via Highlander's syndrome
• Mindless Titans (Attack on Titan)
• Immortals (Baccano)
• Archangels and Devils (Bastard!!)
• Demons (Black Clover)
• Secre Swallowtail (Black Clover); via Anti bird
• Homunculus (Buso Renkin)
• Ichika (Cat Planet Cuties)
• Ewan Remington (Chrono Crusade)
• Demons (Chrono Crusade)
  • Chrono
• Pursuers (Chrono Crusade)
  • Duke Duffau
  • Gurio
  • Carv
• Sinners (Chrono Crusade)
  • Aion
  • Rizelle
  • Genai
  • Viede
  • Shader
• Apostles (Chrono Crusade)
  • Azmaria Hendrich
  • Joshua Christopher
  • Rosette Christopher; Anime only
• Dignified Power Users (Code:Breaker)
• Wen (Cowboy Bebop)
• Road Kamelot (D.Gray-man)
• Unsealed Spirits (Date A Live)
• Sir Isaac Ray Pelham Westcott (Date A Live)
• Brioche d'Arquien/Hina Makishima (Dog Days); originally
• Master Muten Rōshi (Dragon Ball series)
• Mr. Popo (Dragon Ball series)
• Demon King Piccolo (Dragon Ball series)
• Uranai Baba (Dragon Ball series)
• Piccolo Jr. (Dragon Ball series)
• Lord Slug (Dragon Ball Z)
• Androids (Dragon Ball series)
  • Android 17
  • Android 18
  • Dr. Gero (Android 20)
  • Android 21
• Majin Buu (Dragon Ball series)
• Fused Zamasu (Dragon Ball Super); Anime only
• Moro (Dragon Ball Super); via absorbing life force
• Digimon (Digimon)
• Eureka (Eureka Seven)
• Victims of Ankhseram's Curse
  • Zeref Dragneel (Fairy Tail)
  • Mavis Vermilion (Fairy Tail)
• Tōka (Fairy Tail: 100 Years Quest)
• Haruko Haruhara (FLCL: Alternative)
• Homunculi (Fullmetal Alchemist)
• Eva Pilots (Rebuild of Evangelion Films)
• Gendo Ikari (Rebuild of Evangelion Films);via Nebuchadnezzar's Key
• Tuka Luna Marceau (GATE)
• Doctor Chaos (Ghost Sweeper Mikami)
• Sherlock Holmes (Hidan No Aria)
• Immortals (Highlander: The Search for Vengeance)
  • Colin Macleod
  • Kyala
  • Marcus Octavius
• Michael (Highschool DxD)
• Gabriel (Highschool DxD)
• Lord Tenzen Members (Hell’s Paradise: Jigokuraku)
• Sesshomaru (InuYasha)
• Vampires (JoJo's Bizarre Adventure)
  • DIO Brando
• Pillar Men (JoJo's Bizarre Adventure Part II: Battle Tendency)
  • Esidisi
  • Kars
  • Santana
  • Wamuu
• Hampnie Hambert/Kizuna Astin (Kamisama no Inai Nichiyobi)
• Dominiux (King's Raid: Ishi wo Tsugumono-tachi)
• Master Paval (King's Raid: Ishi wo Tsugumono-tachi)
• Nagate Tanikaze (Knights of Sidonia)
• Immortal Ship Committee (Knights of Sidonia)
• Tsumugi Shiraui (Knights of Sidonia)
• Kanata (Knights of Sidonia)
• Sebastian Michaelis (Kuroshitsuji)
• Demons (Kuroshitsuji)
• Shaorin (Mamotte Shugogetten)
• Ruuan (Mamotte Shugogetten)
• Ajimu (Medaka Box)
• Yuta (Mermaid's Forest)
• Mana (Mermaid's Forest)
• Masato (Mermaid's Forest)
• Muromi (Muromi-san)
• Hidan (Naruto)
• Kakuzu (Naruto)
• Sasori (Naruto)
• Ōtsutsuki Clan members (Naruto)
• Albreio Imma (Negima)
• Jibril (No Game No Life)
• Lala-Ru (Now and Then, Here and There)
• Brook (One Piece); via the Yomi Yomi no Mi
• Sugar(One Piece); via the Hobi Hobi no Mi
• Dr. Genus (One Punch Man)
• Fuu Houhou (The Outcast)
• Aces/Barons (Plunderer)
• Archie/Guile Hideout (Pokémon Adventures)
• Kurousagi (Problem Children are Coming from Another World, Aren't They?)
• Ruru Amour/Cure Amour (HUGtto! Pretty Cure)
• Witch of sins (Re:Zero kara Hajimeru Isekai Seikatsu)
• Sin Archbishops (Re:Zero kara Hajimeru Isekai Seikatsu)
• Various Deities (Saint Seiya)
• Maquia (SayoAsa)
• Iorph (SayoAsa)
• Tamala (Tamala 2010: A Punk Cat in Space)
• The Mysterious Postcat (Tamala 2010: A Punk Cat in Space)
• The Ancient Dragon (Seiken Tsukai no World Break)
• The Golden Tyrant/Judas Iscariot (Seikon no Qwaser)
• Merlin (The Seven Deadly Sins)
• Ladylee Tangleroad (Toaru Majutsu no Index)
• Tsukasa Tsukuyomi (Tonikaku Kawaii)
• Some Rankers (Tower of God)
• Immortals/Sennin (Twelve Kingdoms)
• Azuza Aizawa (I've Been Killing Slimes for 300 Years and Maxed Out My Level)
• Toguro Brothers (Yu Yu Hakusho)
• Flame Hazes (Shakugan no Shana)
  • Shana
  • Margery Daw
  • Wilhelmina Carmel

Cartoons/Comics

• Princess Bubblegum (Adventure Time)
• Darwin Watterson (The Amazing World of Gumball)
• Gumball Watterson (The Amazing World of Gumball)
• Yakko, Wakko and Dot (Animaniacs)
• Ms. Bitters (Invader Zim)
• Denizens (Infinity Train)
• Anodites (Ben 10 series)
  • Verdona Tennyson
• Ectonurites (Ben 10 series)
  • Ghostfreak
• Celestialsapiens (Ben 10 series)
• Petrosapiens (Ben 10 series)
  • Diamondhead
• Professor Paradox (Ben 10 series)
• Leaky Leona (Codename: Kids Next Door); via Fountain of Youth
• José (Cybersix)
• Black Adam (DC Comics)
• Raven (DC Comics)
• Shazam (DC Comics)
• Kryptonians (DC Comics); via yellow sun radiation
• Daxamites (DC Comics); via yellow sun radiation
• Wonder Woman (DC Comics)
• Various Metahumans (DC Comics)
• Fairies (Disney Fairies)
• Timmy Turner and everyone else on Earth (The Fairly OddParents)
• Jägermonster (Girl Genius)
• Agent Hunter (Image Comics)
• Experiments/Stitch and his cousins (Lilo & Stitch)
• Ben Grimm/Thing (Marvel Comics)
• Steven Rogers/Captain America (Marvel Comics)
• Olympians (Marvel Comics)
• Extremis Users (Marvel Comics)
• Various Mutants (Marvel Comics)
  • African American mutants
  • Asian mutants
  • Hispanic mutants
  • Native American mutants
  • White mutants
• Various characters (My Little Pony: Friendship is Magic)
• Skips (Regular Show)
• Guardians (Rise of the Guardians)
  • Sanderson Mansnoozie/Sandman
  • E.Aster Bunnymund/The Easter Bunny
  • Toothiana/The Tooth Fairy
  • Nicholas St. North/Santa Claus
  • Jack Frost
• Pitch Black/The Bogeyman (Rise of the Guardians)
• Jack (Samurai Jack)
• The Guardian (Samurai Jack)
• Queen Angella (She-Ra and the Princesses of Power)
• The Ones/Force Wielders (Star Wars)
• Gems (Steven Universe)
  • Garnet
  • Pearl
  • Amethyst
  • Rose Quartz/Pink Diamond
  • Blue Diamond
  • Yellow Diamond
  • White Diamond
  • Spinel
• Practitioners of the Hercules Method (The Strange Talent of Luther Strode)
• Toys (Toy Story series)
• Steven Rogers/Captain America (Ultimate Marvel)
• Century Babies(Wildstorm/DC Comics)
  • Jenny Sparks
  • Elijah Snow
• Superboy (Young Justice)

Live Television/Movies

• Various Mutants (X-Men Movies)
  • En Sabah Nur/Apocalypse
• Adaline Bowman (The Age of Adaline)
• Hypercognitive Alphas (Alphas)
  • Stanton Parish (​Alphas)
• Drogyn (Angel)
• Lorien (Babylon 5)
• Some Witches (Charmed)
• Some Demons and Warlocks (Charmed)
• Whitelighters and Elders (Charmed)
• Darklighters (Charmed)
• Cupids (Charmed)
• Mermaids (Charmed)
• Io (Clash of The Titans 2010)
• Vera Moray/Granny Rags (Dishonored)
• Cybermen (Doctor Who)
• Rory Williams (Doctor Who); as an Auton
• Time Lords (Doctor Who)
  • The Doctor
  • The Master
  • Romana
• Henry Morgan (Forever)
• John Hancock (Hancock)
• Mary Embrey (Hancock)
• Adam Monroe (Heroes)
• Immortals (Highlander)
• Zombies (IZombie)
• Ben Linus (Lost)
• Hugo "Hurley" Reyes (Lost)
• Jacob (Lost)
• The Man in Black (Lost)
• Mother (Lost)
• Richard Alpert (Lost)
• John Amsterdam (New Amsterdam)
• Rumplestiltskin (Once Upon a Time)
• Non-Perishables (Sausage Party)
• Godzilla (Shin Godzilla)
• Sylphs (The Spiderwick Chronicles)
• Angels (Supernatural)
• Archangels (Supernatural)
• Demons (Supernatural)
• Alphas (Supernatural)
• Leviathans (Supernatural)
• Doc Benton (Supernatural)
• Four Horsemen of the Apocalypse (Supernatural)
• Deities (Supernatural)
• Wizard of Oz (Supernatural)
• Powerful Witches (Supernatural)
• Wendigos (Supernatural)
• Phoenixs (Supernatural)
• Golems (Supernatural)
• Djinn (Supernatural)
• Nachzehrer (Supernatural)
• Werewolves (Teen Wolf); via Regenerative Healing Factor
• Alexander Corvinus (Underworld)
• Lycans (Underworld)
• Vampires (Underworld)
• Werewolves (Underworld)
• Original Vampires (The Vampire Diaries/The Originals)
• Enhanced Original Vampires (The Vampire Diaries/The Originals)
• The Beast/Upgraded Original Vampire (The Vampire Diaries/The Originals)
• Vampires (The Vampire Diaries/The Originals/Legacies)
• Original Hybrids (The Vampire Diaries/The Originals)
• Hybrids (The Vampire Diaries/The Originals)
• Powerful Witches (The Vampire Diaries/The Originals); via Spell Casting
• Witches (Witches of East End)
• Warlocks (Witches of East End)
• The Mandragora (Witches of East End)
• Various Metahumans (Arrowverse)
  • Tyson Sykes/Gravedigger
  • Tobias Whale via Anti-Aging Serum
  • Latavious "Lala" Johnson/Tattooed Man

Literature

• Hunters of Artemis (Camp Half-Blood Chronicles)
• Great A'Tuin (Discworld)
• Dragon Riders (The Inheritance Cycle)
• Elves (The Lord of The Rings)
• Gandalf (The Lord of The Rings)
• Gollum (The Lord of The Rings)
• Morla (The Neverending Story)
• Peter Pan (Peter and Wendy)
• Vampires (Shadowhunter Chronicles)
• Warlocks (Shadowhunter Chronicles)
• Sorcerers (Skulduggery Pleasant)
• Oskar Matzerath (The Tin Drum)
• Bebra (The Tin Drum)
• Dark One (The Wheel of Time)
• The Young Guardians (The Young Guardians)

Video Games

• Demigods (Asura's Wrath)
• Chek Summoners (Breath of Fire IV)
  • Abbess
• Vampires (Castlevania Lords of Shadows )
• Trevor Belmont/Alucard (Castlevania Lords of Shadows 2)
• Ghosts (Crypt of the NecroDancer)
• Skeletons (Crypt of the NecroDancer)
• Wraiths (Crypt of the NecroDancer)
• Shelke the Transparent (Dirge of Cerberus)
• Alduin (Elder Scrolls)
• Alcina Dimitrescu (Resident Evil series)
• Dragons (Elder Scrolls)
• Vampires (Elder Scrolls)
• Black Philips (New Blood Interactive's DUSK)
• Fork Maidens (New Blood Interactive's DUSK)
• Turrets (New Blood Interactive's DUSK)
• Dog (Fable II/III)
• Ghouls (Fallout series)
• Generation 3 Synths (Fallout 4)
• Nyx (Fire Emblem Fates)
• Rollermines (Hλlf-Life 2 series)
• Zhuge Kongming (Honkai Impact 3rd)
• Zoe (League of Legends)
• Kokiri Tribe (The Legend of Zelda)
• Ruby (Lunar: Eternal Blue)
• Nall (Lunar: Silver Star Story)
• Quan Chi (Mortal Kombat)
• Shao Kahn (Mortal Kombat)
• Some Pokémon (Pokémon)
  • Legendary Pokémon
  • Artificial Pokémon
• Alex Mercer (Prototype)
• Elizabeth Greene (Prototype)
• James Heller (Prototype 2)
• Zombies (Quake series)
• Mummies (Quake: Dissolution of Eternity)
• Aldra (Queen's Blade)
• Albert Wesker (Resident Evil series); after he is revived by the Prototype Virus his aging process seems to have stopped altogether
• Brain (Skylanders)
• Shadow the Hedgehog (Sonic the Hedgehog)
• Judd (Splatoon)
• Rosalina (Super Mario Galaxy)
• Merasmus (Team Fortress 2)
• The Dryad (Terraria)
• Peter Pan (Valkyrie Crusade)
• Anomalocaris (Valkyrie Crusade)

Folklore/Mythology

• Most Deities (Mythology/Folklore)
  • Viking Deities (Norse Mythology)
• Vampires (Mythology/Folklore)
• Werewolves (Mythology/Folklore)

Web Comics/Series/Original

• Malachite (Channel Awesome - Suburban Knights)
• Jones (Gunnerkrigg Court)
• Cosmic Powers (Red vs Blue)
  • Genkins
  • Chrovos
• Lee Marvin (Welcome to Night Valve)
• Sophia/Olympia/Subject/Zero/Olympia Zero/The Original/Europa (SCP Foundation)
• The Demiurge/The God of Flesh/Važjuma/Saklas/Samael/God-Eater/Devourer/His Undulating Vastness/The Great Winnower/The God of Flesh/Nüwa/The Dragon in the Great Brass Cage/Yaldabaoth (SCP Foundation)
• The Light-Bringer/The Morning Star/He-Who-Made-Dark and He-Who-Made-Light (SCP Foundation)
• The Ambassador of Alagadda (SCP Foundation)
• Khahrahk/Harak/Khnith-hgor/Shormaush Urdal/Son of the Third Brood/The Devourer of Worlds/The Dread/Devourer/The Crimson Monarch/The King who Rose from the Bleeding/Lord of the Throne of Despair/Defiler of Worlds/Rapist King/Proskellion/SCP-001 - Tufto's Proposal - The Scarlet King (SCP Foundation)
• The Brothers Death/The All-Death (SCP Foundation)
• The High Elder Gods (SCP Foundation)
• The All-Mighty (SCP Foundation)
• The Fragmented One/WAN/he Eternal Network/Fuxi/The Maker of Machines/Hakhama/The Great Voice/Sophia/Mekhane/SCP-001 - TwistedGears/Kaktus Proposal - The Broken God (SCP Foundation)
• SCP-001-A - S. D. Locke's Proposal - When Day Breaks (SCP Foundation)
• SCP-008 - Zombie Plague (SCP Foundation)
• SCP-014 - The Concrete Man (SCP Foundation)
• SCP-030 - The Homunculus (SCP Foundation)
• SCP-073 - "Cain" (SCP Foundation)
• SCP-076 - "Able" (SCP Foundation)
• SCP-590 - He Feels Your Pain (SCP Foundation)
• SCP-723-D - Unkillable D-Class (SCP Foundation)
• SCP-993 - Bobble The Clown (SCP Foundation)
• SCP-784-ARC (SCP Foundation)
• SCP-1504 - Joe Schmo (SCP Foundation)
• SCP-1761 - The Republic of Arnold Fitzwilliams (SCP Foundation)
• SCP-1810 - Mr. Pierrot (SCP Foundation)
• SCP-1915 - Status Quo (SCP Foundation)
• SCP-2020 - Cliche, Right? (SCP Foundation)
• SCP-2384 - The Biggest Duck of All (SCP Foundation)
• Mobile Task Force Omega-9 ("The Scrubs")/Gloria Stanfeld (GRRGRL)/Jim Yearden (WTF_STFU)/Thomas Warden (BOOGER)/SCP-2639 - Video Game Violence (SCP Foundation)
• SCP-2776 - Mr. President (SCP Foundation)
• SCP-2872 - A Fast Horse (SCP Foundation)
• SCP-3700-1 - HOMER (SCP Foundation)
• SCP-3700-2 - ANGIE (SCP Foundation)
• SCP-4606 - Deimos (SCP Foundation)
• Aaron Siegal (SCP Foundation)
• Robert Bumaro (SCP Foundation)
• Monica Pinkston (SCP Foundation)
• Samsara (SCP Foundation)
• Grand Karcist Ion (SCP Foundation)
• Slender Man (The Slender Man Mythos)
• Merlin (Stupid Mario Brothers)
• Nox Decious (Stupid Mario Brothers)

Known Objects

• Ice King's Crown (Adventure Time)
• Cure-All Elixir (Baccano)
• Grand Panacea (Baccano)
• Ōken (Bleach)
• Fountain of Youth (Codename: Kids Next Door)
• Smartskin (DC Comics)
• Dragon Balls (Dragon Ball series)
• Wondrous Potion Vial (Epic Seven)
• Font of Immortality (Fablehaven)
• Ring of Winter (Forgotten Realms)
• Muur Talisman (Star War Legends)
• Ambrosia (Toaru Majutsu no Index)

Known Locations

• Neverland (Peter Pan)

Gallery

Cartoons/Comics

Being toons, Yakko, Wakko, and Dot (Animaniacs) are all essentially immortal and ageless. They had a prominent career in the 1930s until they were locked in the Warner Bros water tower, resurfacing in the 1990s without aging a single day.

Professor Paradox (Ben 10) was displaced outside of time due to an "experiment gone wrong", rendering him biologically immortal, never aging nor needing sustenance and sleep.

José (Cybersix) was engineered by his father to have eternal youth, so even though he is chronologically an adult, he remains biologically a child, to prevent rebellion.

Raven (DC Comics)

Timmy Turner (The Fairly OddParents) made a secret wish that everyone on Earth would stop aging so he would stay 10 years old and could keep his fairies forever, though 50 years later the Fairy Council undid the wish when they discovered it.

Jägergenerals (Girl Genius) are the eldest and possibly the original Jägermonsters, making them 600-700 years old.

Stitch (Lilo & Stitch)

Immortus (Marvel Comics) ceased his own aging process by his far-flung futuristic technology.

Benjamin Grimm/The Thing (Marvel Comics)

Skips (Regular Show) is granted eternal youth by the Guardians of Eternal Youth.

As a side effect of Aku's Time Travel spell, Jack (Samurai Jack) was rendered ageless; he has wandered the Earth for 50 years and hasn't aged a day.

Gems (Steven Universe) are hatched from the ground as fully formed adults and do not age further, being able to live indefinitely.

Because he was released from his pod early, Superboy (Young Justice) will never physically age.

Jenny Sparks (Wildstorm/DC Comics) was born "with the century" - on the stroke of midnight on New Year's Eve of 1900. As she grew she displayed certain superhuman abilities and skills, as well as immortality (not aging beyond her 20's)

Elijah Snow (WildStorm/DC Comics)

Princess Celestia and Princess Luna (My Little Pony: Friendship is Magic)

Queen La (The Legend of Tarzan)

Toys (Toy Story series)

Anime/Manga/Manhwa

China (Axis Powers Hetalia) is 4000+ years old but appears much younger due to being the only country that is truly immortal.

Washio (Buso Renkin) is a homunculus, which makes him an ageless life-form, with immunity from diseases, making him very hard to kill.

Papillon (Buso Renkin) is a homunculus, which stops him from aging, and even prevents him from dying from his mortal disease, making him very hard to kill.

Kinjo (Buso Renkin) is a homunculus, which stops him from aging and immune to any mortal diseases and very hard to kill.

Aion (Chrono Crusade).

The Four Founders of Eden (Code:Breaker) are all Dignified Power users, and thus mastered their life force to the point of ceasing their aging.

Kouji (Code:Breaker) is a Dignified Power user and has ceased aging for a long time.

Prime Minister Fujiwara (Code:Breaker) has mastered his life force like the Dignified Power users and stopped aging.

Road Kamelot (D.Gray-man) hasn't aged in 35 years, keeping her preteen appearance forever.

Shinigami (Death Note) will remain eternal, so long as they continuously use their Death Notes to extend their own lifespan when necessary.

Master Muten Rōshi (Dragon Ball series) eats constantly Paradise Grass, which prevents him from dying of old age.

Piccolo Daimao (Dragon Ball) wished for eternal youth, returning to his prime and never aging again...

...a trait his offspring and reincarnation, Piccolo Jr., inherited.

Artificial Humans (Dragon Ball) such as 17 and 18 ceased to age since they are altered at a cellular level, while 16 is synthetic from the start.

Artificial Human 19 (Dragon Ball Z) is a synthetic creation of Dr. Gero who will not age.

Dr. Gero (Dragon Ball) converted himself into an Artificial Human, thus escaping old age for the sake of eternal life.

Majin Buu (Dragon Ball series) has existed since the dawn of time itself and has shown no signs of aging since.

Mavis Vermilion (Fairy Tail) hasn't aged since casting an incomplete Law spell to save her friend Yuri Dreyar life, looking like 13 years old despite being roughly 118.

Tomiko Asahina (From the New World) restores the length of her telomeres, allowing her to extend her life indefinitely.

Demi-goddess Rory Mercury (GATE) retains the appearance of a 12 years old girl, despite being 964 years old.

As one of the first generation of Angels, Michael (Highschool DxD) is over 10,000 years old, having lived since the time of the Biblical God.

As one of the first generation of Angels, Gabriel (Highschool DxD) has lived for over 10,000 years.

Muromi (Muromi-san) is completely ageless, having been alive since Pangaea over 300 million years ago.

Having lived since the First Hokage's era, Kakuzu (Naruto) extended his lifespan by tearing the still-beating hearts out of his victims and integrating them into his own body when it was necessary.

Hidan (Naruto) is the successful product of the Jashin religion's experiments of immortality, and cannot die of injuries, but can die of hunger; in essence, he's the inverse of a typical semi-immortal.

Having converted himself into a puppet, Sasori (Naruto) escaped old age and the need for sustenance intake necessity; the only way to kill him is to attack his core of living flesh.

Zetsu (Naruto) are ageless, as Black Zetsu is an artificial human created from Kaguya's materialized will, while White Zetsu are mutated humans.

Kaguya Ōtsutsuki (Naruto) being a pure-blooded Celestial Being, possesses eternal youth so long as she continues to consume the Chakra Fruit.

Momoshiki Ōtsutsuki (Naruto) being a pure-blooded Celestial Being, possesses eternal youth so long as he continues to consume the Chakra Fruit.

Isshiki Ōtsutsuki (Naruto) being a pure-blooded Celestial Being, possesses eternal youth so long as he continues to consume the Chakra Fruit.

Supported by his Yomi Yomi no Mi's ability, Brook (One Piece) possesses eternal youth, his living cell tissues have already rotted off before he came back to life.

The power of the Hobi Hobi no Mi has given Sugar (One Piece) eternal youth. Despite her appearance, she is actually 22 years old.

Dr. Genus, (One-Punch Man) a centenarian, after rejuvenation.

Archie (Pokemon Adventures) wearing the armor Eternity, which grants him eternal life as the inside has its own timezone.

Kurousagi (Problem Children are Coming from Another World, Aren't They?) is no longer aging and has lived for over 200 years and still has the appearance of 18 years old.

The Ancient Dragon (Seiken Tsukai no World Break) is the most ancient metaphysical of them all, as he has lived completely unchanged by the passage of time for countless ages.

The Golden Tyrant/Judas Iscariot (Seikon no Qwaser) has lived for over two thousand years since the time of Jesus Christ.

Younger Toguro (Yu Yu Hakusho) and his older brother wished to become demons, preventing them from aging.

Elder Toguro (Yu Yu Hakusho) and his younger brother wished to become demons, preventing them from aging.

As the incarnation of the natural world, Lala-Ru (Now and Then, Here and There) hasn't aged in over 600,000 years.

While she has the appearance of a 17 year old, Azuza Aizawa (While Killing Slimes for 300 Years, I Became the MAX Level Unknowingly) is actually the 300 year old "The Witch of the Highlands".

Video Games

Due to being Mystic Zombies, the Fork Maidens (New Blood Interactive's DUSK) have infinite lifespans, though aren't immune to being killed off.

Due to a powerful curse she accidentally placed on herself, Nyx (Fire Emblem Fates) will never age.

Pit (Kid Icarus) has the perpetual appearance of a 13-year old boy.

Engineered to be ageless, Shadow the Hedgehog (Sonic the Hedgehog) is over 50 years old despite his youthful form.

Judd (Splatoon) has (somehow) been alive outside of cryogenic suspension for at least 2,000 years without aging.

Rosalina (Super Mario Galaxy) is ageless and visits earth once every century.

Merasmus (Team Fortress 2) hasn't aged in at least over 6,000 years.

The Hero's Dog (Fable II/III) seemingly never ages.

Peter Pan (Valkyrie Crusade) doesn't age.

Anomalocaris (Valkyrie Crusade) is completely ageless, having been alive since the Cambrian period over 500 million years ago.

Literature

Great A'Tuin (Discworld)

Sméagol/Gollum's (The Lord of The Rings) life was extended far beyond its natural limits by the effects of possessing the One Ring. At the time of his death, Sméagol was about 589 years old.

Morla (The Neverending Story)

Due to living in Neverland, Peter Pan (Peter Pan) never ages beyond that of a 12 year old.

Live Television/Movies

Adam Monroe (Heroes) never aged because of his regeneration.

Mavis (Hotel Transylvania) is a 118-year-old vampire.

Henry Morgan (Forever)

Jacob (Lost) was at the same age for over 2,000 years as a result of becoming the guardian of the heart of the island.

After becoming the smoke monster, The Man in Black (Lost) became ageless.

The Guardians (Rise of the Guardians)

The Non-Perishables (Sausage Party), are three anthropomorphic foods that will never expire/die from old age.

Web Animation/Comics/Original

Jones (Gunnerkrigg Court) is ageless and has existed since the formation of the earth.

By its very physiology, SCP-030 - The Homunculus (SCP Foundation) is immune to aging.

Videos

SCP-030 - The Homunculus (SCP Orientation)

SCP-073 Cain (SCP Animation)

SCP-076 ABLE (SCP Animation)

SCP-993 Bobble the Clown (SCP Animation)

SCP-1440 The Old Man from Nowhere (SCP Animation)

Joe Schmo SCP-1504 (SCP Animation)

SCP-3700 Tides of War (SCP Animation)