Being [[DemonicPossession Demonically Possessed]] [[WillingChanneler rarely]] [[SuperEmpowering works out]] [[PowersViaPossession well]] for the [[HeroicHost host]], however, every once in a while things go FromBadToWorse. Perhaps it's just that EvilMakesYouUgly, EvilMakesYouMonstrous, or that [[GrandTheftMe your body is]] [[EmpathicShapeshifter the plaything of the mind]], but when the body your mother gave you has a new landlord there is a nasty tendency for you to be [[{{Shapeshifting}} remodeled]], and [[BodyHorror possibly]] [[ShowingOffTheNewBody shown off]].

Sometimes justified in narration as the host becoming the new body of the guest either as a intrinsic feature or as a deliberate action on the part of the guest. In extremely unfortunate cases, the host body also suffers from PossessionBurnout which will quickly destroy it.

Compare and Contrast: GlowingEyesOfDoom, PowerUpgradingDeformation, RedEyesTakeWarning, and ViralTransformation

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!!Examples:

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[[folder:Anime and Manga]]
* Apparently happens in ''[[Manga/BlueExorcist Ao No Exorcist]]''. Father Fujimoto is definitely an example. [[spoiler: So is Toudou, later on,]] although it does seem to depend on how powerful the demon in question is.
* ''Manga/{{Naruto}}'':
** This happens to Orochimaru's hosts.
** When Naruto has a demon cloak with four or more tails, the nine-tailed fox is controlling him.
** The Edo Tensei technique works by taking some genetic material of a deceased person and forcing them into a still-living body. This transforms the host's body into that of the deceased person's, killing the host in the process but allowing the body to become animate.
** In Chapter 679, [[spoiler: Kaguya apparently inflicts this on Madara.]]
* [[Anime/FullmetalAlchemist The 2003 anime version]] of ''Manga/FullmetalAlchemist'' had [[spoiler:Dante's]] deterioration with each possession.
* Animals possessed by spirits in ''{{Berserk}}'' get deformed human-like faces
* In ''Manga/{{Bleach}}'', when Kaien is possessed by Metastasia he first gets hollowed, empty eyesockets, then he starts sprouting tentacles from his limbs, sockets and mouth.
* In ''Manga/SoulEater'', when Medusa loses her body, she possesses a young girl and twists her appearance into a younger version of herself.
* ''Franchise/SailorMoon'': Season 3's Mistress 9 has the transformation come in stages. While relatively dormant, her host, Hotaru, [[PossessionBurnout grows steadily weaker]] and while in (brief) periods of direct control, undergoes an EvilCostumeSwitch and GlowingEyesOfDoom with FaceFramedInShadow. After gaining complete control, however, she ages Hotaru's body into her mid-20's and becomes a WomanInBlack with RapunzelHair.
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[[folder:Comic Books]]
* ''ComicBook/JudgeDredd'': The Dark Judges tend to possess people solely to asssist them in finding new corpses for their spirits to occupy after the destruction of the previous one, but Judge Mortis once possessed the Chief Judge and directly decayed his body into the cow-skulled monster that he is.
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[[folder:Fanfiction]]
* In ''[[FanFic/StarWarsParanormalities Star Wars: Paranormalities]]'', this is a common side-effect of Forceless possession. Played for horror in that, unfortunately for the hosts, [[AndIMustScream they are consciously aware of both the possession]] and [[BodyHorror the transformation]].
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[[folder:Films -- Live-Action]]
* Happens twice in ''Film/{{Constantine}}''. In the beginning, when the soldier demon inhabits the young woman her face is covered with blotches. When [[spoiler:Angela Dodson]] is possessed by Mammon (Lucifer's son) near the end the change is much greater. In each case, once the possession ends the skin changes disappear.
* ''Film/TheExorcist'' had a pretty gruesome transformation.
* ''{{Legion}}'': various angels do ''odd'' things to the bodies they inhabit.
* ''Film/TheDevilInside'' plays it straight, but in fairly plausible ways. Those possessed sport freakish flexibility, dilated eyes (a line of dialogue indicates that the human eye can dilate to 9 mm, 11 mm under the influence of some drugs, but possession can force it further), and red eyes. All could be explained by actual physical symptoms.
* The Candarian demons in the ''Franchise/EvilDead'' series use this in a variety of ways.
** In the original film the only change was in the eyes (and spreading black veins in one case), but physical damage inflicted on the host quickly reached gruesome levels.
** ''Evil Dead 2'' had a greater degree of BodyHorror, including a possession victim with an ''extremely'' long neck.
** ''Army of Darkness'' had [[spoiler: Sheila]] suffer some minor changes in bone structure when [[spoiler: she]] was possessed, and the rest of the Deadites took on a rotted appearance even without any injuries.
** Finally, the 2013 remake only gives the possessed yellow eyes by default, but they then inflict gruesome injuries on ''themselves'', apparently to match the documented appearance of whatever spirit is possessing them.
* Happens to the Chosen One in Creator/JohnCarpenter's ''Film/PrinceOfDarkness''. Satan, in the form of an evil green fluid, enters the mouths of his victims to control them, but the Chosen One ingests the lion's share of the fluid and becomes the [[GrandTheftMe personal vehicle of Satan himself.]] (This causes said Chosen One's body to appear progressively rotten and decayed as the movie goes on.)
* In ''Film/DemonKnight'', this is the fate of everyone possessed by demons. The last transformation in the film [[spoiler:of a young boy]] is especially grotesque.
* ''Film/ANightmareOnElmStreetPart2FreddysRevenge'': Every time Freddy possesses Jesse, he forcibly converts Jesse's body into his own form.
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[[folder:Literature]]
* True for most Denarians in ''Literature/TheDresdenFiles'', though some of them choose to keep their human appearance.
* PlayedWith in ''[[Literature/TheSpaceTrilogy Perelandra]]'', [[spoiler:Dr. Weston]]'s possessed body at first looks quite normal but as it is damaged beyond repair in the course of the plot (yet continues to move thanks to the devil inside it), it becomes horrible to look at and wholly inhuman.
* In ''Literature/InheritanceCycle'', when a human is possessed by spirits and becomes a Shade, it transforms their appearance, including turning their hair bright crimson.
* Professor Quirell from ''Literature/HarryPotterAndThePhilosophersStone''.
* ''Literature/{{Spellbent}}'': Possession victims get funky eye colors. Their sclera (white of the eyes) turns red or in some cases purple, depending on the power level of what's possessing them.
* In [[NightsDawn Night's Dawn]], possessors ''can'' reshape their hosts' bodies, but ''shouldn't'' because it's carcinogenic.
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[[folder:Live-Action TV]]
* In ''Series/StarTrekDeepSpaceNine'', when the Pa-Wraiths possess someone, the person's sclera's become red.
* In ''Series/KamenRiderDenO'' being possessed by any of the friendly --taro imagin gives the character a lock of appropriately colored hair and sometimes a change in wardrobe.
* Demonic possessions eventually tend to disfigure the host in ''Series/BuffyTheVampireSlayer'' and ''Series/{{Angel}}''.
* On ''Series/DoctorWho'', when the Master [[BodySurf steals the Trakenite consul Tremas's body]], he de-ages it by several years, restyles its hair, beard, and clothing, and causes a pair of black leather gloves to appear from absolutely nowhere in the process.
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[[folder:Tabletop Games]]
* ''DungeonsAndDragons 3.5'' & 4.0: Many fiends find remodeling their new body to their advantage and extensive remodeling can result in being completely replaced.
* In ''TabletopGame/{{Warhammer40000}}'', Daemons will alter the body of their host, moulding it into one more suitable for them. The host rarely lasts for very long.
* In ''TabletopGame/DemonTheFallen'', Demons knowledgeable in the lore of transformation can make permanent alterations to its host.
* The Fomori in ''TabletopGame/WerewolfTheApocalypse''. When a bane (an evil spirit of the Wyrm) possesses a human body, that person's body is hideously mutated with whatever the Storyteller picks from a grab-bag of disgusting BodyHorror-based powers. Examples include multiple limbs and mouths, corrosive puss boils, and internal organs replaced by infectious fungus.
* Likewise, the spirits in ''TabletopGame/WerewolfTheForsaken'' can do this to their hosts, but only at the point where they've either destroyed the host's consciousness or irreversibly taken over their soul. In any case, the body starts to take on elements of the spirit possessing it - for the Hosts, this is usually the creature the Host derives from (examples include spiders, rats, crows, worms, fungi, etc.), but for the Spirit-Claimed, the possessed takes on elements of its nature (a fire elemental will give its host bright eyes and blisters, a death spirit will make its host look gaunt, etc.).
* ''TableTopGame/YuGiOh'': However, getting too full of himself, "Poseidra" put on the bracelet, and instantly his body began to change, and the "Mermail" King spoken of in legends appeared. "Poseidra's" body was [[DemonicPossession taken over by the king residing in the bracelet]]. The king eliminated the "Atlantean" army with ease. It appears that "Abysstrite" [[SealedBadassInACan sealed the bracelet away]] because [[HumanSacrifice the advent of the king required a sacrifice]].
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[[folder:Videogames]]
* In ''VideoGame/{{Diablo}}'', this happens to Prince Albrecht when he is possessed by Diablo, and following the hero's sticking of Diablo's soulstone into his own head, he winds up possessed as well, and becomes the new Diablo in ''VideoGame/DiabloII''.
* In ''VideoGame/{{Doom}} 3'' (and, quite possibly, the old Doom games) demonic possession turns people into zombies.
* This happens to anyone possessed by a demon in ''Franchise/DragonAge''.
* ''VideoGame/LegacyOfKain'': Raziel learns to occupy corpses and shape them into an image of himself.
* When an Ing from ''VideoGame/MetroidPrime 2'' fuses itself to a host, the host takes on a darker, mutated appearance as a direct result.
* ''VideoGame/SuperRobotWarsUX'': [[spoiler: Noval Dilan becomes the physical embodiment of Kali Yuga (with Durga's appearance) and grows to the size of a planet]].
* In ''VideoGame/ShinMegamiTenseiIV'', reading certain kinds of books will transform the reader into demons; this trope is implied in the process. It's most clearly seen in the case of Ogun and Dantalion, though Issachar and the victims of Red ingestion might also count.
[[/folder]]

[[folder:Webcomics]]
* [[spoiler: Vaarsuvius]] from ''Webcomic/TheOrderOfTheStick'' [[spoiler: takes on a demonic appearance after being [[http://www.giantitp.com/comics/oots0635.html Soul Spliced]] with three epic-level casters.]]
* Emily from ''Webcomic/OurLittleAdventure'' took on a horrid alien appearance as some kind of controlling, [[spoiler: Angelo loyal]] parasite inside her took control of her body.
* AMI from ''Webcomic/RedSpaceBlues'' took over an enemy soldier by first impaling than replacing his head with her own [[http://redspaceblues.com/?comic=red-space-blues-27]].
* In {{Paranatural}}, the host of a spirit (whether human or object) will gradually begin to look like its host, albeit in barely significant ways.
** Isaac's only manifestation is his hair, which is [[http://www.paranatural.net/index.php?id=113 SPIKY ALL ON ITS OWN]]
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[[folder:Web Originals]]
* Noted in the WhateleyUniverse as one possible consequence of a low-powered Avatar-type mutant hosting a too-powerful spirit as the spirit will make changes to the Avatar's body to make itself more comfortable. And the [[HeroicHost Avatar]] trait is ''already'' all about being superhumanly good at this sort of thing...
[[/folder]]

[[folder:Western Animation]]
* After being possessed by Zordrak in an episode of ''TheDreamstone'', Amberley gains a pair of extremely evil looking glowing eyes.
* ''WesternAnimation/JackieChanAdventures'': the ghost of Shendu (a [[NinjaPirateZombieRobot dragon-demon-wizard]]) usually gives his host glowing red eyes when in control. While he's not capable of transforming his host's body under his own power, he once tried to do so ''manually'' with potions.
* In ''WesternAnimation/AdventureTime'', [[ArtifactOfDoom the Ice Crown]] causes a physical transformation in its wearer, whom it tries to impose its own will on. As the person falls further and further under the Crown's control, they begin to develop blue skin, long white hair, and fangs (although some of these traits can vary depending on circumstance).
* Happened a few times in ''WesternAnimation/TheRealGhostbusters'', most notably in the episode 'If I Were A Witch Man', where we see the ghostly-witch Kestral possess two people - one of which being Egon Spengler - and she turns their bodies into the old stereotypical witch look (or in Egon's case, an old man).
[[/folder]]

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