History Main / MoodSwinger

* To say that ''[[VisualNovel/DanganronpaTriggerHappyHavoc Danganronpa]]'''s [[spoiler: Junko Enoshima's]] mood changes on a dime is putting it '''''[[{{Understatement}} very]]''''' [[Main/{{Understatement}} lightly]]. [[spoiler: She gets so soul-crushingly bored that she changes her outward personality at a moment's notice because she becomes disinterested even with how she's presenting herself, cycling rapidly between regal, hot-blooded, scholarly, cutesy, and depressed.]]

** Thunder [=McQueen=] from ''Manga/JojosBizarreAdventureStoneOcean'', a PsychopathicManchild who's easily brought to tears from joy or sadness. When Ermes first meets him he bursts into tears over forgetting where he hid his stolen money, then when she shows concern he begins gushing over how he'd like to marry a woman like her before immediately lamenting that it'll never happen and [[DrivenToSuicide attempting to kill himself]]. Granted he had valid reasons to be upset considering he was imprisoned for a crime he didn't commit, but it's made clear that it's partially due to him being HisOwnWorstEnemy.

* ACDC from ''Manga/JoJosBizarreAdventure'', even admitting that he's the most emotional of the Pillar Men. When Joseph [[spoiler:cuts off his arm and destroys it so he can't reattach it]], his reaction is to... [[InelegantBlubbering burst into tears and cry like a little girl]], and then after a while stop as quickly as he started and claim he was just blowing off steam. This actually makes him dangerous; Joseph reads his opponents to get the upper hand on them, but it's impossible to read ACDC's constant mood shifts.

* ACDC from ''Manga/JojosBizarreAdventure'', even admitting that he's the most emotional of the Pillar Men. When Joseph [[spoiler:cuts off his arm and destroys it so he can't reattach it]], his reaction is to... [[InelegantBlubbering burst into tears and cry like a little girl]], and then after a while stop as quickly as he started and claim he was just blowing off steam. This actually makes him dangerous; Joseph reads his opponents to get the upper hand on them, but it's impossible to read ACDC's constant mood shifts.

* PlayedForDrama in the film of ''Film/WaterForElephants.'' [[spoiler: August's temper]] is pretty infamous among the other circus workers; he goes from charming and polite to [[BerserkButton violently mad]] in the blink of an eye, and can't seem to control it. While the other workers call him a "paranoid schizophrenic," the setting's time period[[note]] (the 1930s, when proper medical care and especially psychology was just getting started) [[/note]] mostly likely means that ''something'' is wrong with him, but [[AmbiguousDisorder people just don't know what it is.]]

* Basil from ''WesternAnimation/TheGreatMouseDetective'' certainly swings from manically happy to crushingly depressed and back to manically happy again quickly. Of course, this is because he's based on SherlockHolmes, who was possibly bipolar, and definitely a massive cocaine addict. So either Basil could use a little lithium, or he's gotten into a bad, mouse-sized vial of seven per cent solution (an expected hazard of living under Holmes' floor).

* ''WesternAnimation/MiraculousLadybug'': Duusu, kwami of the Peacock Miraculous, can go from exuberant cheer to bawling her eyes out and back again at a moment's notice. Of course, he is the AnthropomorphicPersonification of ''emotion'', so it makes some sense.

* On ''Series/BabylonFive'' [[TheCaligula Emperor Cartagia]] can go from goofing around like a decadent party animal to ordering your execution within the span of five minutes[[note]]five ''seconds'' if you say the wrong thing at the right moment[[/note]]. Suffice it to say, his DeadlyDecadentCourt has a hell of a time figuring out which way to jump to keep in his good graces.

* ''Series/GameOfThrones'': Over the course of a single torture session, Ramsay can swing wildly between emotionless droning, absent-minded contemplation, childish glee, and psychotic rage.

For even more extreme cases, see HairTriggerTemper, SplitPersonality, JekyllAndHyde, TheSociopath, {{Tsundere}}, {{Yandere}}. Not to be confused with MoodWhiplash, which is a trait of the ''storytelling'', not an individual character. They may also end up singing a SongOfManyEmotions.

* Rena from ''VisualNovel/HigurashiWhenTheyCry''. This and the fact that she's a NightmareFetishist seems innocent enough at first, but then you find out she's a GrotesqueCute {{Yangire}} best known as the "Cleaver Girl" for her AxCrazy tendencies. [[spoiler:[[GroundhogDayLoop Sometimes]]]]. The games hint she has a disorder, as she's shown to take pills back when she lived in Ibaraki and suffered from paranoia and hallucinations [[spoiler:caused by Hinamizawa Syndrome, but her doctors had no way of knowing that since only very few people know about its existence so they treated her symptoms instead]]. However, it's exaggerated [[spoiler:especially due to {{Unreliable Narrator}}s]] so it [[RuleOfScary seems freakier]].

* Rena from ''VisualNovel/HigurashiWhenTheyCry''. This and the fact that she's a NightmareFetishist seems innocent enough at first, but then you find out she's a GrotesqueCute {{Yandere}} antagonist best known as the "Cleaver Girl" for her AxCrazy tendencies. [[spoiler:[[GroundhogDayLoop Sometimes]]]]. The games hint she has a disorder, as she's shown to take pills (and [[spoiler:it can't be for Hinamizawa Syndrome, which is taken in shots]]), but it's exaggerated [[spoiler:especially due to {{Unreliable Narrator}}s]] so it [[RuleOfScary seems freakier]].

* To say that ''[[VisualNovel/DanganronpaTriggerHappyHavoc Danganronpa]]'''s [[spoiler: Junko Enoshima's]] mood changes on a dime is putting it '''''[[{{Understatement}} very]]''''' [[Main/{{Understatement}} lightly]]. [[spoiler: She gets so soul-crushingly bored that she changes her outward personality at a moment's notice because she becomes disinterested even with how she's presenting herself, cycling rapidly between regal, over the top excited, scholarly, cutesy, and depressed.]]

* [[PhysicalGod Misao Mikogami]] from ''Kami Kaze'' can be a [[GenkiGirl fairly cheerful and fun-loving]] teenage girl, [[TheParagon nice to anyone who needs a hand]], and will stand up for someone when they need it. Say the wrong thing around her and [[HairTriggerTemper her mood will change so fast]] that you won't even have the time to mouth the words OhCrap before you're standing under an ocean of water with your current surroundings gone so far beyond the GodzillaThreshold that you'll be glad you're not around [[ApocalypseHow to see the aftermath]]. [[FromBadToWorse And that's not counting the times]] you've [[UnstoppableRage pissed her off enough]] that she decides [[FateWorseThanDeath to play around with you for a little while]]. She's the ''nicest'' deity [[CrapsackWorld in this series]].[[note]]The nastiest go straight through the MoralEventHorizon on [[ButForMeItWasTuesday your average Tuesday]] and don't even look back [[CrossesTheLineTwice to see where the line went]].[[/note]]

* Harry of ''Manga/OutlawStar''.

* Naomi in ''Manga/ZettaiKarenChildren'' started off being the calm, sweet girl all the time. Once she realized that her [[DirtyOldMan supervisor Tanizaki's]] [[WifeHusbandry treatment]] of her was why she was having trouble with her powers, she lets loose and from then on shows no restraint in throwing him into a wall when he gets too close. Her CodeName even changes from "Kitty Cat" to "Wild Cat" in the process.

* [[{{Webcomic/Homestuck}} Sollux]] is this in canon, but [[UpToEleven even more so]] in the fanadventure ''Webcomic/BeTheSeaDwellerLowblood''. He and Karkat will get in a fight, one of them will apologize, the other won't accept, then the second one apologizes and the first one ignores him, they get into another fight, one of them will apologize but be rejected ''again'', one will think about apologizing but change his mind, one will beat himself up over not apologizing sooner but then not go through with it, etc, etc, etc.

* In ''FanFic/MegaManReawakened'', Tron Bonne has been like this since Arc 5 began--and it's revealed it's because [[spoiler:she's pregnant]].

* The Whistleblower DLC for ''VideoGame/{{Outlast}}'' has Eddie Gluskin, also known as the Groom. Having been sexually abused by his uncle and father as a child, he became obsessed with sexuality and marriage, and was already a serial killer before coming to the asylum. The experiments conducted on him there only made him worse. When you finally meet him, he has already mutilated and killed dozens of other (male) inmates, turning them into his 'brides' - and he attempts to do the same to you. He fluctuates from using creepily loving terms ("Darling!") to crazily misogynistic ones ("Filthy sluts. You're like all the others.") to outright death threats ("You don't deserve my children. You don't even deserve to live.").

* To say that ''[[VisualNovel/DanganronpaTriggerHappyHavoc Danganronpa]]'''s [[spoiler: Junko Enoshima's]] mood changes on a dime is putting it '''''[[{{Understatement}} very]]''''' [[Main/{{Understatement}} lightly]]. [[spoiler: She gets so soul-crushingly bored that she changes her outward personality at a moment's notice because she becomes disinterested even with how she's presenting herself, cycling rapidly between regal, over the top excited, cutesy, and depressed.]]

* Sachiko from ''LightNovel/MariaSamaGaMiteru'' may be an AloofDarkHairedGirl but she's prone to this nevertheless. She acts aloof or mean randomly and often pushes her friends away. Sachiko herself lampshades this when, in the third season, she questions when Yumi became so good at handling her.

[[quoteright:350:[[WesternAnimation/{{Tangled}} https://static.tvtropes.org/pmwiki/pub/images/RapunzelMoodSwing_3762.jpg]]]]

* [[NamesToRunAwayFromReallyFast Ivan the Terrible]] had mood swings as a side effect of the quicksilver he used to treat his pain. One bipolar episode had him beat his son to death in a fit of rage. He reacted with devastating sadness. (Indeed, Ilya Repin's painting of him forms the current page image for MyGodWhatHaveIDone.)

** Pheobe was like this with her pregnancy hormones in "The One With The Worst Best Man Ever".

* ''[[VisualNovel/DanganronpaTriggerHappyHavoc Danganronpa]]'''s mastermind takes this UpToEleven, as their ''entire personality and tone of voice change with their mood''. To say that they're emotionally unstable [[Main/{{Understatement}} is putting it]] '''''[[{{Understatement}} very]]''''' [[Main/{{Understatement}} lightly]].