Sealed Inside a Person-Shaped Can

So there is some cosmic being locked away so that it cannot interfere with the outside world. Some sort of powerful being... good, evil, or neither, it doesn't matter. But this time, they didn't lock away the being in a magical jar of some sort. Rather, they somehow managed to bind the thing into the body of a person. A person who may, or may not, be aware that they are carrying around some dangerous being within them.

Unleashing the cosmic being usually results in the "can" either dying or being subsumed into it, or killing the "can" results in the destruction of the being. Occasionally causes a Battle in the Center of the Mind. Occasionally results in a Superpowered Evil Side, for the evil, neutral and Knight Templar examples. Reincarnation may be involved.

A Subtrope of Sealed Evil in a Can, Sealed Good in a Can, and Sealed Badass in a Can. Contrast Grand Theft Me and Demonic Possession. Compare Living MacGuffin, Apocalypse Maiden, Barrier Maiden, and Treasure Chest Cavity, as well as Caged Inside a Monster, where someone is trapped within something else's body in a directly physical, rather than extradimensional or spiritual, sense. May be caused by Supernatural Sealing. See also Restraining Bolt. Evil beings sealed this way are almost always a Leaking Can of Evil. Compare and contrast with Trapped in the Host.

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Examples:

Anime & Manga

• Teito Klein, the protagonist of 07-Ghost, is Pandora's Box... and imprisoned inside Pandora's Box is the death god Verloren.
• The main premise of Bastard!! (1988): a boy named Rushe Renren contains within him the spirit of one of the most powerful sorcerers of all time, the infamous Exploder Wizard... Dark Schneider!
• Bleach: Urahara didn't know how to destroy the Hougyoku so he placed it inside the soul of a spirit being (Rukia). By forcing Rukia to undergo a transformation into an ordinary, physical human, the Hougyoku would be forever sealed. It's strongly implied he actually did this to bait Aizen into revealing his true face since Aizen was forced into the open to recover the Hougyoku before Rukia fully transformed. Aizen eventually fuses completely with the Hougyoku. There's no known way to separate them which makes Aizen almost unkillable. As a result, Aizen has been sealed for 20,000 years in Soul Society's most powerful prison.
• In Bungou Stray Dogs, Nakahara Chuuya's body is basically the human container and controller of the godlike power 'Arahabaki' that manifests itself as Chuuya's power. It can also partially take control of his body by enhancing this power, but slowly breaking him down.
• In Cardcaptor Sakura, Yue, one of the two Guardians of the Clow Cards is sealed inside Yukito Tsukishiro, though it's more of a transformation rather than being sealed inside a different person.
• In A Certain Magical Index, Touma's body contains... something that is more powerful than a guy who was more powerful than God. Touma's right hand, Imagine Breaker normally keeps it in check. Whenever his right hand is severed, the being escapes but is resealed when the hand is reattached or, more commonly, regenerates on its own. Interestingly, it's implied that there may be more than one being inside Touma. On two occasions, a white dragon emerged, and on the second of these, it brought seven others with it as well. In all other cases, something invisible has emerged. The second one appears to fluctuate greatly in power, as it's been crushed easily by two different villains to demonstrate their power.
• In Deadman Wonderland, the Red Man AKA the Bad Egg is sealed inside Shiro. This isn't a case of possession or split personality of any sort, though it initially looks this way and Shiro intentionally makes it seem like that's what it is; while it may seem like her ditzy Genki Girl persona is the "real" one, she's just putting up a front and spending as much time with Ganta as she can before it all goes to hell.
• In Defense Devil, Idamaria's body contains the goddess of Hell.
• A rather unusual case happens in The Demon Girl Next Door. Sakura's core is sealed inside Yuko. She actually did this to herself to boost Yuko's health. Yuko would die if it was removed before Yuko has the power to resist her family's curse alone. The unusual thing being the entity being sealed is this universe's Big Good, and Yuko, the "person-shaped can" in this case, is a demon (although only technically so).
• Digimon Ghost Game has a peculiar example in Regulusmon, the Jet-Black Champion. While the body he is sealed in was originally his, an alternate personality formed and eventually took over under unknown circumstances, essentially coming to be the Gammamon seen in the series proper. Regulusmon does eventually retake control, but after being defeated in a Battle in the Center of the Mind, he is once again sealed inside Gammamon.
• The warrior Tapion and his little brother in the Dragon Ball Z movie, Wrath of the Dragon, had half of a beast each sealed inside them, and in turn they were sealed inside a magical music box, a wizard kills Tapion's little brother and frees the other half from Tapion himself, and Tapion is soon unsealed as well and ends up in Earth. In the end Goku manages to kill the beast without trapping it, which frees Tapion forever so he can live his life as he sees fit.
• Fairy Tail:
  • The main example of this trope is a gigantic spoiler - but here's the idea anyway: The first-generation Dragon Slayers contain their dragon parents that disappeared! Specifically, they sealed themselves inside their children in order to create "antibodies" that would ensure they wouldn't become crazy and omnicidal dragons like Acnologia and to prolong their own lives after Acnologia fatally wounded them.
  • It comes up again in Fairy Tail: Dragon Cry with Animus being revealed to be a dragon fatally injured by Acnologia that sealed himself inside of the dying Sonya to save himself, which also saved her life and extended her lifespan. Unlike the Dragon Slayers' parents, who could leave their children at any time thanks to them possessing Dragon Magic, Animus couldn't since Sonya wasn't a Slayer, and thus he needed to obtain the Dragon Cry to free himself and maintain his existence.
• Hell Teacher Nube has a demon who tried to kill him in his childhood sealed into his left hand by his mentor Minako.
• High School D×D: Draig, the Welsh/Red Dragon is sealed inside the protagonist, Issei. Or rather Draig, and his counterpart Albion the Vanishing Dragon, were both sealed inside 'cans' called Sacred Gears, which pass on to a new host when the previous host dies. A case of Sealed Can in a Person Shaped Can. Draig and Albion are neither Good or Evil, but their constant fighting with each other caused 3 separate warring factions to team up in order to seal them.
• In Inuyasha Second Movie: The Castle Beyond the Looking-Glass, Kohaku is revealed to have Naraku sealed within a scar on his back.
• The story of Jujutsu Kaisen starts off with The Hero Yuji Itadori ending up hosting the Big Bad Sukuna within his body after accidentally eating one of the twenty fingers containing his power. As a result, Sukuna occasionally gets involved in his fights through Demonic Possession and will use his Story-Breaker Power to make things even worse for him.
• In the first season of K, after the main character Yashiro Isana regains his memory of being the Silver King and being body-snatched by the Colorless King,( he is still in the body of a random high school boy that the Colorless King body-snatched before swapping with him), he decided to trap the Colorless King inside of himself this way or, more precisely, the body of the high school boy that the Colorless King body-snatched before him. He then steps in between the Red and Blue kings as they're fighting, and lets the Red King destroy his body to kill the Colorless King. Good thing he's immortal.
• Miss Kobayashi's Dragon Maid: For a good chunk of the series, Kanna has a large amount of mana from a 'dragon ball' that she broke as a prank sealed inside her. She can't actually use it though, due to it being compressed (Kobayashi compares it to an unopened zip file).
• In My Balls, there is a powerful demon sealed in the main character's left testicle.
• Naruto: The Jinchūriki are people who have tailed demons sealed inside them. They include the title character, Naruto, Gaara of the Desert, and Killer Bee (who contain the Nine-Tailed Fox, the One-Tailed Tanuki, and the Eight-Tailed Ox, respectively). Removing the tailed beast typically kills the host within minutes after the fact, and if the host dies with the beast still sealed inside it then it can take the beast some time to reform. As a result, the beasts grant their hosts supernatural power both to avoid pseudo-death and to weaken the seal. It's worth noting that being sealed in a human makes them more dangerous. Most Bijuu (Tailed Beast(s)) simply avoid humans and, due to their size and power, have little need for strategy. Jinchūriki can access their power and utilize years of training to focus it more effectively. Though, as the Eight-Tails and Nine-Tails have shown, they're quite capable of learning to use tactics, and of acting like tag-team partners with their Jinchūriki.
• Ayanami Rei from Neon Genesis Evangelion is claimed (by one character) to be carrying the soul of the second Angel, Lilith, inside her. Her associated powers are similar to those of the Angels, so it's probably true.
• Rosario + Vampire both plays this trope straight and inverts it. Inner Moka remains sealed by the rosary she wears, but she's the original, and Outer Moka is an artificial personality, so she's effectively sealed inside her own body.
• Sailor Moon:
  • Prince Endymion tries to do this with Metaria near the end of Pretty Guardian Sailor Moon but she ends up possessing him instead, causing Sailor Moon to have to kill him. Temporarily.
  • In the '90s Sailor Moon anime, Sailor Galaxia sealed Chaos inside herself to protect the universe from it, but ended up turning evil from its influence instead and trying to take over the galaxy. Note this only happened in the anime; in the manga, Galaxia was a willing collaborator with Chaos to conquer the galaxy out of her own lust for power.
• In Sasami: Magical Girls Club, the "cauldron" holding all the witches' negative emotions turns out to be an actual person, as the negative emotions were too powerful to be held by anything other than a pure heart.
• Shakugan no Shana:
  • A major plot-point is that Artifacts of the Crimson World are often hidden inside 'Torches', who are sort of like temporary simulacra of people killed by Crimson Lords and placed to make their disappearance unnoticeable.
  • The Flame Hazes, concerning their "masters". If they were to get out of their host, the Flame Haze will explode and die.
• Slayers:
  • Rezo's eyes are a can for Shabranigdo.
  • Gaav, the Demon Dragon King was sealed in a human. The seal leaked, and it might be said that it leaked both ways, since this is what caused Gaav to revolt against the other demon lords in the first place. A common fan theory goes that the gods knew Humanity Is Infectious, and chose to imprison defeated demons in familial lines of people specifically as a failsafe, so that the Always Chaotic Evil would be diluted out over the generations.
  • In the series' backstory and novel series, Lei Magnus and Luke are people-shaped cans for pieces of Shabranigdo. Since Shabby was split into seven pieces, we can assume that there are four others like them that we don't know about.
• In Sorcerer Hunters, the main character Carrot has the God of Destruction sealed within him.
• Nia Teppelin from Tengen Toppa Gurren Lagann is a sleeper for the anti-spiral.
• In Tokyo Mew Mew, Masaya Aoyama was created specifically as a can for alien entity Deep Blue.
• From The World God Only Knows, The Weiss (who enter a gap in the host heart) and the Goddesses (who feed on The Power of Love).
• In YuYu Hakusho, the demon Kurama placed his soul into the body of a human fetus before it could get its own soul.

Comic Books

• Puck of Alpha Flight (the original, Eugene Judd), once served as a walking prison for a demon whose life-draining power resulted in his original dwarfism.
• In Billy Batson and the Magic of Shazam, after Billy seems to be slowly becoming more nasty and violent, it's revealed that Mr. Mind has been living in his subconscious since being defeated in the previous series.
• Mia of Death Vigil is a teenage-looking girl who was bound to a True Primordial from beyond the Veil in order to save her life. She can transform into the Primordial's monstrous form, though she is reluctant to do so without her father's guidance to keep her humanity intact.
• In ElfQuest, when Big Bad Winnowill finally gets killed, her spirit would be free to prey on the other elves... except that Rayek, the one elf who truly loves her and hopes for her redemption, pulls her spirit into his own to prevent her doing more harm.
• Etrigan the Demon is sealed by Merlin inside Jason Blood.
• In Green Lantern: Rebirth, previous events involving Hal Jordan having gone kind of Ax-Crazy over the loss of his hometown, killed most of the Green Lantern Corps, renamed himself Parallax, and eventually ending up as the host for The Spectre were retconned: according to the new telling, Parallax had always been an entity unto itself, and possessed Jordan to use his power and anger for its own purposes. The Spectre getting involved turned the whole situation into more of a person-shaped-can scenario, with Jordan as host for both of them but the Spectre serving to keep Parallax stuck within him and unable to escape or exert any real control.
• In Johnny the Homicidal Maniac, Johnny is revealed to be a "Waste-Lock", a human that serves as a form of receptacle for the spiritual negativity that humans generate by their very existence. This turns out to be the reason why Johnny never ends up getting caught for any of the horrid things he does and also (partially) explains why he's so utterly messed up. After the thing he was keeping locked up escaped during volume 5, he is freed from his duty once the universe is rebooted. It seems to do little to him except remove some of his compulsion to kill things and making people more aware of his existence.
• In Judge Death's first appearance in Judge Dredd, Dredd seals Death in Judge Anderson's body by encasing her in Boing, a spray-on, clear, rubber-like substance that, despite totally enclosing the person's body, nevertheless allows the person to breathe normally for no explained reason. She's done this trick on several other occasions when facing the Dark Judges, but only temporarily: the evil killer ghost judge in her head isn't exactly passive with the arrangement.
• Marvel Comics has legendary Planet Eater Galactus, who acts as the seal keeping the Eldritch Abomination Abraxas imprisoned and not destroying the multiverse. He only needs to eat planets in the first place because the seal is powered by his metabolism.
• The Naruto parody Raruto pokes fun at this: the fourth Bigboss^note Yep, that's Hokage meant to seal the Kyubi in an urn, but there wasn't any non-living container at hand's reach, so he used a baby.
• Sleepwalker is a psychic alien from the Mindscape, a dimension that connects the minds of everything living in the physical world, who protects the minds of humans from demons and nightmares. When his demon Arch-Enemy traps him in the mind of Ordinary High-School Student Rick Sheridan, Sleepwalker is able to manifest in the physical world while Rick sleeps or is unconscious. He becomes a superhero protecting the humans' physical bodies and lives the way he protected their minds in the Mindscape.
• X-Men Vol. 3 #15.1 features a woman who had trapped several demons in her body.

Fan Works

• In The Chronicles of Narnia fic “Across the Worlds", Zaru, the Talking Leopard, becomes the unwilling guardian of the Deplorable Word (The Magician's Nephew); the Word remains in his mind and often tries to compel him to speak it, but this ensures that the Great Darkness cannot use the Word to destroy other worlds. Zaru only uses it once when he has trapped one of the most powerful agents of the Great Darkness and a couple of dying allies in an already dead world where there is no other life to destroy. Even after this, the Word still attempts to compel Zaru to speak it again, but he resists the urge, with the goddess Artemis complimenting his strength of will in a manner that makes it clear the Word would be this to most people.
• In Avengers: Infinite Wars, Celeste Morne is introduced as the living prison for the Muur Talisman, keeping the essence of Karness Muur and the Rakghoul outbreak contained within herself so long as she maintains her self-control. Once she starts travelling Earth with Bucky, the Force eventually leads her to Kamar-Taj, where the Ancient One is able to free Celeste of the burden of the Talisman and lock it in the Order's archives.
• In the canon of The Bridge we get an example of a villain container for an even worse villain with Monster X as the vessel for Kaizer Ghidorah. While Monster X is an Anti-Villain with a sense of honor and is genuine friends with his teammates, Kaizer Ghidorah is a rampaging monstrosity that will kill anything around him. A big part of Monster X's story arc is both finding out about Kaizer's existence and keeping him contained.
• In Hunters of Justice, to prevent Trigon from being a threat ever again, Raven seals him in her chakra, ensuring that he will never escape as long as she lives, and when she does eventually die, Trigon will perish with her.
• In the backstory of Imperfect Metamorphosis, the Shadow Youkai proved too tough for Yukari and Co. to kill it outright, so they wiped its memories and De Powered it into a more manageable form. Over the decades Rumia developed her own personality, so when the former attempts to reemerge it has to fight the latter (and Rin Satsuki) for control. Bonus points for including a Battle in the Center of the Mind, which didn't end well.
• In Midnight Sun, the main character Faratrass is used as a seal to contain the Demon King and is taught magic to contain him. The Trauma Conga Line she goes through during the story ends up putting an emotional strain on her to the point where the seal begins to weaken.
• Past Sins: As revealed in "Tainted Blessing", about 3/4ths of the way through the story, foul magic is being imprisoned inside a pony:
  the purpose of the white geometric designs that crisscrossed Nexus’s body. It was a binding spell, meant to hold a majority of the tainted magic.
  
  Nexus, the real Spell Nexus, had turned his body into a living prison [for the corrupting magic].
• Pony POV Series:
  • In the Dark World timeline, this trope is attempted and subverted during the Boss Battle with Odyne!Cruelty. Rarity tries to remove Cruelty's soul from the body she's possessing and using her Element of Desire to seal it inside herself, but Cruelty fights her off.
  • The Shining Armor Arc reveals that Minuette is actually the Master transformed into a pony with his consciousness sealed in a fob watch. And she refuses to become him again. Unlike many examples in the end she manages to prevent him from escaping and feeds him to the Blank Wolf, erasing him from existence and freeing herself from him for good.
• At the end of Rolling in Beaches, the remnants of the Rainbow of Darkness are sealed inside Spike after they use the Elements of Harmony to destroy it. The Princesses keep this to themselves, though Rodi is reluctant, as she sees this as a potential risk.

Films — Animation

• The Dazzlings in My Little Pony: Equestria Girls – Rainbow Rocks are sirens from Equestria who were banished and imprisoned in human bodies by sending them to the human world. Further illustrated by their "Magical Girl" Transformation Sequence, which looks less like a transformation and more like a ritual to release something unspeakably evil.

Films — Live-Action

• In Dogma, Almighty God herself took a vacation in the form of a mortal man. When that shell was beaten into a coma and put on life support, God was trapped inside. To be released, the shell had to be taken off of life support, and thus killed.
• Elvira for Elura in Elvira's Haunted Hills.
• Ghost Rider is treated as this in Ghost Rider (2007) by Johnny Blaze, his human form.
• In Malignant, it's revealed that Gabriel was originally a parasitic twin who shared a brain with his sister Emily. He developed strange psychic and electrokinetic powers, and not only that, but he could also alter Emily's perception of reality on demand. Eventually, Gabriel grew so powerful that doctors made the decision to remove as much of him from Emily as possible, ultimately sealing him inside his own sister's skull alive and conscious for decades, though he could still occasionally take control over her from within.
• Calypso in Pirates of the Caribbean, sealed inside Tia Dalma. She is fully aware of her true nature, however.
• In Tales from the Darkside: The Movie a man meets a woman after surviving a gargoyle attack. The Gargoyle doesn't kill him on the Promise not to tell anyone. Years later he tells the woman who is now happily his wife, with children. it's revealed the woman is the Gargoyle who sadly kills him because he broke the promise, and takes their children also gargoyles to live in sadness.

Literature

• Chasing the Moon: While Fenris' world-destroying self is trapped in the form of a second moon in the sky, its rational mind takes the form of a conspicuously human looking being named Calvin.
• At the end of The Last Dark, the finale The Chronicles of Thomas Covenant book, Covenant seals God of Evil Lord Foul inside himself. He hopes that eventually he'll be able to change Foul's nature, but ends up withdrawing from the world in order to keep Foul from finding a way to hurt the people around him for the meantime.
• Discworld:
  • In the first few books, Rincewind has one of the Eight Spells of Creation hidden inside his head. It's described as trying to escape, and it has filled his head to the point of him being unable to learn any other spells.
  • After Snuff Samuel Vimes forced the Summoning Dark (basically the Dwarven Anthropomorphic Personification of Revenge, sans anthropomorphism) to obey him rather than the other way around.
• The first sub-series of Dragonlance: The New Adventures involves an evil wizard using this as an attempt to access the power and knowledge of a particularly evil ancient sorceress. Sadly for him, it turns out that Evil Is Not a Toy.
• Felix Castor has a friend that suffers from this. The friend made the mistake of calling up what couldn't be put down, and Felix tried to exorcise it best he knew how — only to find the thing had gotten tenterhooks into his friend's soul, meaning a proper exorcism would kill him. So he did the best he could and knitted them together.
• In The Girl from the Well, the woman in black is sealed within Tark's body by five mystic tattoos, and must murder five people to free herself. The miko Chiyo had also habitually used herself as a person-shaped can for evil spirits, and ended up becoming the woman in black when they overwhelmed her.
• Played in The Girl Who Drank the Moon against the titular character Luna, who has reality-warper scale magic at age five but zero control. Her magic, her knowledge of magic, and her ability to learn about magic (effectively Luna's adult form) are all sealed until she reaches thirteen.
• The reason why the Red Woman goes to the trouble of resurrecting Ned every time he dies in In the Company of Ogres is because he is the mortal vessel of the Mad Void, a universe-destroying Ancient Evil that could potentially do that to their world should it ever escape.
• N. K. Jemisin's Inheritance Trilogy: When the God of Chaos Nahadoth was defeated and enslaved by his brother, he was trapped in two forms — by day, he's an ordinary human with no memory of his true self; by night, he can take his divine form but is still bound to his masters' will. As chaos incarnate, being forced into a static form was more torturous than the subsequent 2000 years of enslavement.
• Angleton is a willing, self-aware case of this, as revealed in the third The Laundry Files book, The Fuller Memorandum. Bob Howard does this to himself to avoid being possessed by something worse.
• In Pale, the Hungry Choir, a Ritual Incarnate that preys upon the hungry or those hurt by hunger, is eventually sealed within Brie Callie, one of its victims. Brie gains the ability to temporarily summon aspects of the choir to defend herself, which take the form of Creepy Children Singing with bloody mouths and broken teeth.
• Invoked and played with as the main plot device in Fiona Patton's Tales of the Branion Realm series, in which a fire god, the Living Flame, essentially inhabits the ruler of an alternate Britain, hopping to the next-in-line whenever one dies. However, they use the Flame's power for the good of the realm, letting it out while (theoretically) keeping it under control. Played straighter in the third book, when the royal family converts to a different faith which regards the Flame as a demon, and deliberately locks it within themselves. Its own followers set out to release it into the body of a believer by seducing its current vessel.
• In A Wizard Abroad, Ronan has the latest incarnation of Lugh, The One's champion, sealed inside him. The Champion was previously sealed inside of a parrot, Peach.
• In G.S. Denning's Affectionate Parody of Sherlock Holmes, Warlock Holmes: A Study in Brimstone, Holmes has trapped the soul of Professor Moriarty within his own body. As a detective, Holmes is a bumbling fool, but Moriarty takes over his voice from time to time in order to contribute his own observations about the cases. Unfortunately for Holmes and Watson, Moriarty pulls a Grand Theft Me at novel's end.
• In Wings of Fire, doing this to his enemies is a favorite trick of Chameleon. He uses an enchanted scroll to transform Hailstorm and Tourmaline. into other dragons with a false identity and memories.

Live-Action TV

• Angel: Illyria.
  Illyria: This fate is worse than death. Condemned to live out existence in a vessel incapable of sustaining my true glory. How am I to function with such limitation?
  Lorne: Have you ever tried a Sea Breeze?
• Buffy the Vampire Slayer
  • The Hell-Goddess Glory, was imprisoned inside a mortal man named Ben, and protected by an enchantment that made any human (vampires and demons were immune) who learned of their connection to forget it quickly. In the end, Rupert Giles smothers Ben to put an end to Glory's threat forever.
  • Dawn: The anti-Glory "Key" that was hidden by being transformed into a girl living in this world, placed under protection of the Slayer. The "can" was lucky in this case: after the Key had served its purpose, it went out of existence, but Dawn remained as a real girl.
• Chilling Adventures of Sabrina: According to Madame Satan and Nick Scratch, the human body is the most powerful prison for demonic spirits that God ever developed. We get to see this put into effect at the end of Season 1, when Nick allows himself to become a container for Satan, with Lilith putting him/them under a sleep spell for added measure before dragging them back down to Hell.
• Doctor Who gives us a couple of good examples in the same season:
  • "Human Nature"/"The Family of Blood" gives us John Smith, a mild-mannered Englishman who teaches at a boy's school and clumsily works to win over the affections of the school nurse while keeping a diary of the various strange things he sees in his dreams. What he doesn't know is that those dreams are the memories of the Doctor, who used a special watch to seal himself away and transform his body into that of a human in order to hide from pursuers. When he learns this, and also that he needs to turn back into the Doctor to prevent the aliens from destroying the school and the surrounding town, he's heartbroken and terrified.
  • "Utopia" has a similar example, Professor Yana, who in this case is unwittingly the Master.
• In the finale of season 4 of Heroes, Sylar was trapped in Matt Parkman's head, while Sylar's body walks around thinking it's Nathan Petrelli, with all of Sylar's and Nathan's powers. That lasts a few episodes before he inevitably escapes.
• Kamen Rider Blade: Hajime Aikawa, a.k.a. Kamen Rider Chalice, is in reality the Joker Undead, a creature that serves as the Reset Button for the "Battle Fight", a battle royale among the Joker and 52 other Undead (each of which represents a different form of life) to determine what will become the dominant life form. The reset triggers with the sealing of all other Undead save Joker, and would result in the end of all life on the planet (at which all other 52 Undead would be unsealed and the Battle Fight would restart). Hajime keeps his Superpowered Evil Side sealed with the Change Mantis and Spirit Human cards.
• The angel Anna from Supernatural was reborn in a human body, and was completely oblivious to the fact that she had great power, even without her Grace.
• The Twin Peaks spirit BOB is somewhere between this and Demonic Possession.
• Van Helsing (2016): In the series finale, Vanessa absorbs the Dark One's essence into herself and then goes into another death-like coma like she started the series in, trapping the darkness inside her indefinitely.

Tabletop Games

• Eberron: Because true immortals have Resurrective Immortality, this is one of the few ways to put them down for good. There are always the same number of demons, angels, and so on in the universe, and if you kill one it will just return to its plane and be reborn into a similar form. The ogres of Borunan in Sarlona fought on the side of the angels in the Forever War, and their greatest warriors trapped demons inside themselves in order to redeem them, becoming the oni in the process. The kalashtar did something similar, taking in the Ascended Demon quori in order to keep them safe from the other quori, who wanted to kill them so that they would reincarnate as evil again.
• Mage: The Awakening: One old God of Fire was cast down by archmages in The Time of Myths, its power sealed in a dormant volcano and its consciousness trapped without its memories as a human in a cycle of Reincarnation.
• Warhammer 40,000 has Daemonhosts, daemons that hijack a person's body to manifest in our reality, which can also be done deliberately, binding a daemon into a prepared body to bind it and use its power for themselves. This is of course horrifically dangerous, as when it escapes the daemon will not be happy with whoever bound it. In Eisenhorn killing the host without simultaneously banishing the daemon simply allowed it to transfer to another host, and while official Inquisition policy is that the person is killed when their body is taken over, one daemon claims they still remain (not that daemons can be trusted).

Video Games

• The "Whytechurch Murderer" in Arcanum: Of Steamworks & Magick Obscura is eventually revealed to be an ancient wizard who tried to banish a powerful demon, and ended up with the demon sharing his body.
• In Bayonetta 2, it turns out that Father Balder, the villain from the previous game, was this for the evil half of the former God of Humankind, named Loptr. The overload of unadulterated evil was what turned him into a monster in the first place.
• The DomZ, local Eldritch Abominations of Beyond Good & Evil, consume the life-force of people harvested/kidnapped from the planets they attack. They've had to step up their eating habits and are attacking Hillis because the spiritual energy of one of the most powerful DomZ beings has been locked inside Jade, the player character.
• Castlevania: Aria of Sorrow and Castlevania: Dawn of Sorrow has Dracula reincarnate as a voice inside Soma Cruz's head. In both Bad Endings, Dracula is fully unleashed, and Soma ceases to be.
• In Devil Survivor, it turns out Amane had a demon sealed inside of her when she was just a child. Unfortunately, said demon is one of the Bels... not the biggest of the problems caused by this, obviously, but considering the whole fight for the Throne of Bel. Poor Amane also has a higher tier angel stuck in her to help balance out against the Bel.
• In Diablo lore, it is customary for the Prime Evils to spend time inside human hosts — either as a safety measure, or chained there against their will. When the Wanderer was tricked into using Diablo's soulstone on himself, he became the unwitting host of the Lord of Terror, and at some unknown point in time lost his will for good. In the distant past, a mage by the name of Tal Rasha decided to bind himself to Baal to imprison the Lord of Destruction forever and ever. While Tal Rasha was eventually possessed by Baal just like the Wanderer, he'd also allowed himself to be placed in magical restraints, which held - until he was released by a third party.
• In Disgaea 2, through the "reincarnation" option, Rozalin is Overlord Zenon and still has the latter's original personality buried deep beneath her own personality. Laharl learns the hard way that unleashing it is a really, really bad idea.
• Dragon Age: Origins has a possible ending where the soul of the Archdemon, formerly Urthemiel, Dragon of Beauty, can end up inside Morrigan's unborn, darkspawn-tainted fetus. If this option was taken, in Dragon Age: Inquisition, you eventually meet this "can" in the form of Morrigan's ten year old son, Kieran, who's a fairly nice boy despite being the host to an Old God—he does, however, make many cryptic remarks, and he appears to be much more ordinary if he was conceived without the ritual taking place. Later in the game, Flemeth takes the Old God soul out of him, leaving him relatively unharmed in a subversion of the usual trope.
• In The Elder Scrolls series backstory, before recorded history, Jyggalag, the Daedric Prince of Order, grew powerful. The other (chaotic-leaning) Daedric Princes grew fearful and jealous of his growing power, so they came together and cursed him into becoming his own antithesis - Sheogorath, the Daedric Prince of Madness. However, at the end of every Era, Jyggalag is allowed to return to his true form in an event known as the Greymarch. During this time, he retakes and destroys the Shivering Isles (Sheogorath's and formerly his own Daedric realm), only to return to the form of Sheogorath at the end. The main plot of the Shivering Isles expansion to Oblivion is Jyggalag attempting to break this Vicious Cycle once and for all. He succeeds in a Literal Split Personalities fashion, freeing himself by passing the mantle of Sheogorath onto the Champion of Cyrodiil.
• Five Nights at Freddy's 3 has a disturbing example with The Purple Guy, his undead corpse sealed inside a rotting springlock suit of Spring Bonnie, hence his now name... Springtrap.
• Hollow Knight: The Final Boss of the game, hidden away in the Black Egg Temple, is the Hollow Knight, who like the Player Character was a "Vessel" created by the Pale King to contain the plague that destroyed Hallownest. In "The Hollow Knight" ending, the PC slays the Hollow Knight and takes his place as the one containing the infection.
• Gilvaroth, the Eldritch Abomination Big Bad of Jeanne d'Arc, is willingly put inside King Henry V's body to protect him from his political enemies by Duke Bedford, Henry V's own uncle. However, Gilvaroth cannot be destroyed As Long as There Is Evil, and a new vessel must be found. Enter Roger, who had the Reaper Ira sealed inside him earlier, and volunteers in order to atone. Things go awry as Gilles takes his place at the last second... with horrible consequences according to Real Life history. Whew! Gilvaroth gets around.
• In the Kingdom Hearts franchise, the hearts of many people take refuge, willingly or not, inside the main protagonist Sora for one reason or another, though for most of them he's not aware of it. The Big Bad Xehanort also counts, except that he does the reverse deliberately subjugating others to his will for the sake of his schemes, though he ends up in this trope proper a couple of times as a result.
• In Might and Magic: Heroes VI, Kiril, the protagonist of the Inferno campaign, ends up sharing his body with Azkaal, a demon prince of destruction.
• In Mortal Kombat, thousands of souls; including the souls of King Jerrod, Kitana's father; & starting from Mortal Kombat X, Shao Kahn himself; are sealed inside Ermac.
• In Persona 3, the "sealed evil" is Nyx, an Eldritch Abomination and Anthropomorphic Personification of death — while the "can" just so happens to be the main character.
• In Phantasy Star IV, the third incarnation of Dark Force is sealed up inside Seth, who joins your party. Creepier than most, in that it's never made clear whether Seth was ever really human, or if he was just a human form. On the one hand, he seems genuinely terrified when he starts to change; on the other, his skill list is 100% dark servitor.
• Prayer of the Faithless: The final fate of the Big Bad Gauron is for his soul to be sealed into Aeyr, allowing the latter to maintain his Revenant powers and survive the Fog.
• In RuneScape, the demon Agrith-Naar is sealed into the human body Denath by priests to render him powerless. To get around this, he gathered a group of dark wizards to summon a fellow demon, Delrith; when the player slays Delrith, he tricks them into thinking that he is in the Infernal Dimensions, and the player tries to summon him into the mortal plane to kill him, but instead send him back to his home plane, making him far more powerful.
• In Sonic the Hedgehog (2006), Princess Elise served as Iblis' "can", with her control over her sorrow being the lid — if she cries, the can is opened and Iblis is unleashed upon the world once more.
• At the start of Soul Nomad & the World Eaters Gig is moved from the Onyx Blade to Revya.
• Tales Series:
  • Tales of Hearts has the Big Bad's mind trapped in the main character. The Dragon finds this out at the beginning of the game and spends the entire first half trying to get him possessed.
  • Tales of Arise: Late in the game it's revealed that three hundred years ago a piece of the Great Astral Spirit was sealed inside Naori, Shionne's ancestor. The seal worked, and the piece even makes the current bearer unkillable, but now it's weakening, which results in Shionne having her "Curse of Thorns".
• In Warcraft lore, Aegwynn was tricked into unwittingly becoming this for the spirit of Sargeras, the series' Big Bad. After defeating his physical form, his spirit entered her body and was later passed to her son, Medivh, who under its influence opened the Dark Portal to allow the Horde to invade Azeroth. Killing Medivh banished Sargeras' spirit back to the Twisting Nether.
  • A very similar arrangement occurs in World of Warcraft. After Arthas is defeated in-game, the heroes realize that his willpower was the only thing preventing the Scourge from launching a frenzied, full-force attack that would annihilate all life on Azeroth. To prevent this from happening, there has to be a Lich King. Highlord Bolvar, the former human faction leader, agrees to take on the role of "Jailor of the Damned".
• Wild ARMs 2 has two of these. The first is a demon sealed inside the protagonist early in the game, which is kept in check by a magic sword that sealed the same evil in a more standard can hundreds of years ago. Since that worked out so well, the same thing is planned for the Kuiper Core, the main threat of the second disc. Unfortunately, the Kuiper Core is a living universe, so the can immediately goes from person-shaped to Eldritch Abomination. At least you can stab it now.
• In Xenoblade Chronicles 1, Zanza is sealed inside of Shulk. It's the reason Shulk can use the Monado and see the future.
• In Yu-Gi-Oh! Reshef of Destruction, this is subverted. Tristan is believed to be trapped in a Monkey Robot by Kaiba or Reshef, but he is just absent, and the weak Monkey Robot is coincidentally as weak as Tristan.

Webcomics

• The cruel Bear Witch from Charby the Vampirate tried to use the Ducayne twins to cheat death after being killed by a rival but Mye was able to tear his soul in two, trapping his essence in her and her brother. It was not a perfect fix and the old wizard is still working on ways to revive himself.
• Played strangely in Digger. The eventual Big Bad is a demon... sealed in a god. Which has in turn been sealed beneath the earth.
• Drowtales: In the final chapter, what is left of Snadhya'rune's demonic spirit is trapped inside Demon!Laele.
• Lovely Lovecraft: The Outer Gods, most notably Nyarlathotep and Azathoth, have mysteriously been trapped on Earth in humanoid bodies.

Web Original

• In The Chronicles Of Oz, unlike the source material in which Tip is just Princess Ozma under a spell that turned her into a boy, Ozma is instead sealed inside Tip, who was created by magic, and unleashing Ozma means Tip gets to cease to exist. And of course, this becomes the only way to save Oz.
• Dreamscape: Melinda's final fate as Ghost Melinda is being encased in an orb of energy created by Eleenin, Kai, and Melissa, which is trapped within the pocket dimension contained within Keedran's chest.
• In The Gamer's Alliance, Laverna, the Goddess of Thieves, is trapped inside the body of Haruko Mizushima who is at first unaware of the predicament although she realizes it later on when the goddess talks to her while she's asleep.
• In Kickassia, Doctor Insano is presented as one of these to Spoony. His inevitable release is a Crowning Moment of Awesome yet still vaguely disturbing.
• In the SCP Foundation, SCP-231 plays this trope for extreme horror. They have to do SOMETHING horrific to this absurdly young girl a minimum of once a day to keep said evil inside. Each time one gets out (or the host dies) it's progressively worse, to the point that hers could mean Earth says adios. Word of God says it's ten times worse than whatever your guess is.
  • And it isn't shy about not-so-subtly hinting at where you should begin guessing. She is, at the very least, repeatedly and violently raped (possibly while being subject to other tortures), while being forcefully kept conscious so she can't escape the pain. She is fed through a feeding tube and gets water through an IV so she doesn't experience the pleasures of eating, and she is never to be given any medication to dull her pain (and is only to be attended to by doctors who haven't taken the Hippocratic Oath). They wipe her memory every couple of days so her surprise, shock, and sensitivity to pain never drop; with careful timing, they do so when her feelings of despair reach their absolute peak and she is given no time to acclimatize.
  • Almost everyone involved with the project begs for a high-class amnesiac to erase the memory of what they've seen, and individuals are to be regularly cycled out of the project for risk of going insane.
  • In the short story "Fear Alone" it turns out that by the time six out of the original seven hosts were dead, the Foundation realized it needed to change its approach, or else it was only a matter of time before SCP-231-7 died as well. Eventually, they discovered that the sealed evil can't actually tell what Procedure 110-Montauk is, or even what it feels like to the host, it only understands that a lot of people are terrified of it. And it turns out, all that is needed to keep the evil contained, is for it to believe something terrifying is happening. And thus, the Foundation does its best to convince everyone else, even us, that Procedure 110-Montauk is some indescribably horrible event.
• Venturian Tale: Jimmy Casket is trapped inside Johnny Ghost, but it is debatable whether he is this trope, or merely a Split Personality.
• Michael Waite, famed horror writer in the Whateley Universe, turned out to be one of these. Locked inside him is The Kellith, a Great Old One foretold to wipe humanity off the planet and repopulate it with her spawn. Then he 'died' and changed into what everyone assumes is a vampiric girl mutant codenamed Carmilla. Kellith did a pretty good job of being not-evil... or at least, not destroying-all-existence evil.

Western Animation

• Adventure Time: After being splashed by healing blood, The Lich regrows his organs and skin and loses his memory of being evil, taking the form of a giant, benign baby known as Sweet P. The Lich is occasionally able to take back control, but these occasions are infrequent and don't last very long, as Sweet P's personality actively fights back.
• The Fairly OddParents!: When Timmy wishes Vicky was good, her evil is shown to be the result of a bug that possesses humans by crawling up their butts. Its ultimate goal is to destroy humanity by infecting someone of high enough influence to make this possible. Timmy is unable to capture the bug and in desperation tells good Vicky, who willingly sacrifices herself to save humanity from being nuked. The bug is thus unable to possess anyone else and Vicky returns to evil.
• In Kung Fu Panda: Legends of Awesomeness, the mighty demon Ke-Pa has been imprisoned for a hundred years by the power of the Peach Tree of Heavenly Wisdom in the body of a pig. When the tree dies, Ke-Pa breaks free and assumes his true form: a giant dragon.
• The Legend of Korra revealed that the origin of the Avatar was the Spirit of Light, Raava, getting bound to Wan, who became the first Avatar.
• Jean Grey was the "can" for Dark Phoenix in X-Men: The Animated Series. Whether this is the case in the original comics depends on which retcon is considered canon at the moment.
• The Owl House: It's revealed in season 2 that that Eda's Owl Beast curse is this; the Owl Beast is actually a separate being that was sealed within a scroll, and then transferred into Eda when Lilith used the scroll to curse her.
• Winx Club: In Episode 23 of Season 3, Valtor is weakened by the Water Stars and Bloom is ready to destroy him, but he warns her not to; Valtor then tells Bloom he cast a spell which caused her birth parents, Oritel and Marion, to be trapped in a spell within his body, and if he is killed, then she will kill her parents as well. The next episode reveals that this was a lie, and her parents are alive and exiled in an unknown dimension somewhere.

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