History SuperpoweredEvilSide / AnimeAndManga

* Double-subverted (at least) in ''Super Taboo'' with [[NiceGuy Yuu]] turning into [[GoodEyesEvilEyes "Instinct Yuu,"]] which is less OmnicidalManiac and more the personification of AllGirlsWantBadBoys that's initially ''desired'' by his mother and sister since that side awakens whenever he's sexually aroused [[WhatDidIDoLastNight (minus everyone being drunk on Christmas)]] and implied to be [[LikeFatherLikeSon inherited from his father,]] whose [[CompellingVoice voice is even mesmerizing enough for amazing phone sex with his wife.]] Other than the confusing blackouts and [[MyGodWhatHaveIDone reactions to sleeping with various women]] it/he's harmless until [[TookALevelInJerkass getting too rough with his sister,]] requiring a BattleInTheCenterOfTheMind where Reason and Instinct (previously just a running gag where Instinct curbstomps Reason in cartoon-form ex. Barney-like dragon eating a knight) are personified as a BettyAndVeronica that he has to choose between despite EvilIsSexy. He finally chooses to be with Reason and rewarded with one last shot at his mom as himself (who's somehow a virgin) before being more steady with his [[BrotherSisterIncest sister as a happily ever after.]]

** [[spoiler: Natsu, as it turns out, is the true identity of E.N.D., the most powerful demon ever created by the BigBad, Zeref, with the intent of [[DeathSeeker killing him]]. It was insinuated even [[WorldsStrongest Acnologia]] was leery of E.N.D.'s true power, and when he briefly comes out he [[CurbStompBattle completely overwhelms]] [=DiMaria=], who wields the power of a ''god'' in a fury.]]

** Also Rogue, whose magic causes the darkness in his heart to manifest as his shadow, tempting him to do evil and even possessing him once to give him a power up and try to force him to kill.
** [[spoiler: Natsu, as it turns out, is the true identity of E.N.D., the most powerful demon ever created by the BigBad, Zeref. While not much else is known about him, its indicated that even the dragon Acnologia is leery of him, which no doubts says a lot about E.N.D.'s power level.]]

** Usually, an inner demon can only emerge if the hero is enraged and can still be resealed with Heroic Willpower. Sukuna and Yuji's situation has limits: Yuji can't control Sukuna's actions once he unleashes him, and if Sukuna doesn't consent to the initial switch, Yuji physically can't take back control from Sukuna for at least a few minutes.
** In any other series, the demonic force can be weaponized and used to give the Hero more strength to defeat an opponent. The one time Yuji tries to use Sukuna as a powerup, it's a disaster. Calling on his guest to help him exorcise a Special Grade, Sukuna at first wanted to team up with the beast and use it to kill Yuji and Megumi at once. After it attacks him, he opts to simply kill the Curse. Which he does, easily. When Itadori is unable to reassert himself, Sukuna immediately goes rogue and attacks Fushiguro, nearly killing him and then successfully killing himself and Yuji in the effort. This incident teaches Yuji that Sukuna is not his friend and can't be used like a weapon.
** Many examples are usually berserkers who mindlessly attack their host's opponent and are eventually revealed to not be as malevolent as they first appear. Sukuna is frighteningly sober and deeply, genuinely evil: Anytime he's given control, the results speak for themselves.
** In a number of series, this "evil side" can sometimes be tamed through The Power of Love and/or The Power of Friendship. Sukuna has proven time and time again that this means nothing to him, the best example being when Yuji begs for his help in saving Junpei, and Sukuna outright refuses. While it's implied there was a practical reason for this, Sukuna simply wanted to hurt the boy instead of comforting him.
** Sometimes (especially in their initial appearance) the super powered evil side has a Godzilla-style sense of territoriality and can be trusted to at least attack the biggest threat (read: whatever Arc Villain forced the hero to unleash the evil side) first in a variation of "Enemy Mine". Not Sukuna. He will sit down and let the bad guys keep on killing everybody For the Evulz. He only fights when they challenge or piss him off in some way, and he consistently makes things worse after he’s done.
** [[spoiler: Worst of all, he doesn't even need Yuji in the long run and will gladly go for a more gifted vessel, given the chance. As the Culling Games prove that any potential Sorcerer can be fed Cursed Objects contained a Sorcerer, Sukuna uses his Binding Vow made early on to take control of Yuji, knock Kurusu unconscious, and force-feed Megumi one of Yuji's fingers containing his essence to use him as a host instead. Essentially, as long as a single finger is out there, Sukuna can play Hot Potato with hosts.]]

** Worst of all, he doesn't even need Yuji in the long run and will gladly go for a more gifted vessel, given the chance. [[spoiler: As the Culling Games prove that any potential Sorcerer can be fed Cursed Objects contained a Sorcerer, Sukuna uses his Binding Vow made early on to take control of Yuji, knock Kurusu unconscious, and force-feed Megumi one of Yuji's fingers containing his essence to use him as a host instead.]] Essentially, as long as a single finger is out there, Sukuna can play Hot Potato with hosts.

** Worst of all, he doesn't even need Yuji in the long run and will gladly go for a more gifted vessel, given the chance. [[spoilers: As the Culling Games prove that any potential Sorcerer can be fed Cursed Objects contained a Sorcerer, Sukuna uses his Binding Vow made early on to take control of Yuji, knock Kurusu unconscious, and force-feed Megumi one of Yuji's fingers containing his essence to use him as a host instead.]] Essentially, as long as a single finger is out there, Sukuna can play Hot Potato with hosts.

** Worst of all, he doesn't even need Yuji in the long run and will gladly go for a more gifted vessel, given the chance. As the Culling Games prove that any potential Sorcerer can be fed Cursed Objects contained a Sorcerer, Sukuna uses his Binding Vow made early on to take control of Yuji, knock Kurusu unconscious, and force-feed Megumi one of Yuji's fingers containing his essence to use him as a host instead. Essentially, as long as a single finger is out there, Sukuna can play Hot Potato with hosts.

* ''Manga/JujutsuKaisen'' '''Horifically [[DeconstructedCharacterArchetype deconstructed]]''' with Sukuna Ryomen who inhabits the protagonist Yuji's body. In most series this trope is a benefit to the heroes even if it's dangerous. '''Well that's not the case here.'''

* In ''Manga/JujutsuKaisen'', Itadori has Ryomen Sukuna, the strongest cursed being, as his super powered evil side. Itadori's journey is about getting and consuming all of Sukuna's fingers, so that he can hold all of Sukuna within him and be executed, destroying him once and for all.

* The Inverse Form of the different Spirits in ''Literature/DateALive'' can be seen as this. Whereas a normal Spirit draws their power from an Angel, an Inverse Spirit draws its power from a Demon King. Examples seen in the anime up to Season 4 include Origami's Metatron/Satan and Nia's Raziel/Beelzebub. It is also worth noting that Inversion happens when the Spirit's happiness drops to a low enough level. Additionally, Inverse Forms are typically far more powerful, more aggressive, impossible to control and have DarkerAndEdgier outfits and weapons.

* Akira Fudou and Amon from ''Manga/{{Devilman}}'' may be the oldest example in the history of manga. And also an UnbuiltTrope, as the manga shows that having one wouldn't just conveniently let you send it out on enemy too strong for you to take -- taking Amon's powers changes Akira from meek and gentle boy into complete BloodKnight and that even without letting Amon out. Amon however only breaks free in a SpinOff manga ''AMON'', and an OVA of the same title. In the anime Amon '''[[spoiler: eats a little girl alive]]''' and in the manga he is maybe just a bitter AntiHero, but still destroys several ''countries'', just by [[WalkingWasteland passing through them]].

** Korrina's Lucario goes absolutely berserk after gaining the power of Mega Evolution because it can't control the aura that's unleashed. Eventually ,it learns to control its power.

* Mob's ???% form in ''Manga/MobPsycho100'' comes out when Mob falls unconscious, and is not only far more powerful than Mob at even 100%, but is also far less restrained in how it uses that power -- though, as a defense mechanism, it doesn't seem actively malicious.

* Ryner Lute from ''Anime/TheLegendOfTheLegendaryHeroes'' is lazy but if you hurt one of his friends, you will see why Alpha Stigmas are feared: an evil God of Destruction personality with overwhelming powers will just disintegrate you.

* Mayo Kagura from ''LightNovel/MaiHimeDestiny''. In a series where everyone has {{psychic powers}}, it's hard to stand out when you have boring ol' telekinesis... unless you have a Super-Powered Evil Side that can ''uproot trees and use them as weapons''.

* [[spoiler:Misa Iliorogue]] from ''LightNovel/TheMisfitOfDemonKingAcademy'', as her Superpowered Evil Side is [[spoiler:Avos Dilhevia, the False Demon King of Tyranny]]. [[spoiler:This is because as a spirit, whose natures is [[ClapYourHandsIfYouBelieve based on the belief of people]], she becomes Avos when she assumes her true form, as the lore of the Demon King of Tyranny gives the powers, abilities, weaknesses and personality of the Demon King of Tyranny as it is believed by demons and humans.]]

* Orson from ''Roleplay/RecordOfLodossWar'' is a Berserker Class and, when he gets angry, with the influence of the demon Hyuri he becomes an unstoppable killing machine that wields a massive claymore as if it were a toothpick.

* Himura Kenshin from ''Manga/RurouniKenshin'' is a TechnicalPacifist in battle, fights with a reverse-blade sword and vowed years ago to never kill again. But if things seem to be getting out of hand even for him to handle (usually when his friends are in danger), his fighting style and mindset slowly begin changing into the highly pragmatic and ruthless Battousai, the assassin he was ten years ago. He switches the extremely humble ''sessha'' for the brash ''ore'', loses the ''de gozaru'' from his speech, his eyes turn gold and more slanted and he moves for the kill. In the anime, Battousai seems to be considered an actual personality Kenshin has learned to seal off by creating his rurouni persona -- he has to punch himself in the face to push it back and revert back. In the manga, this gets lampshaded a bit when Kenshin remarks that his face muscles have cramped and he isn't able to end his permanent death glare.