Psycho Supporter

A psycho supporter follows someone else's beliefs simply because the supporter is nuts.

Used a lot to deconstruct other tropes, most notably the Genki Girl, The Dragon, and The Renfield. Also precipitates many a Face Heel Turn, although this may not necessarily be so.

May also intersect with the Poisonous Friend, Yandere, and Lady Macbeth. A lot of Psycho Supporters also suffer from Mad Love or the Subordinate Excuse if they're really devoted to the leader in question. Contrast Stepford Smiler.

Anime

 * Itsuki from the Yu Yu Hakusho anime loves Sensui because... Sensui is beautiful. In all kinds of senses, with a stress on the functional beauty of tremendous power.
 * In the manga, where Itsuki is more twisted, it's because he's gotten the opportunity to see all that purity get twisted and warped and spit out a shattered genocidal maniac who's more powerful than ever and still charismatic and brilliant. He compares it to "a little girl who believes babies come from storks growing up to star in pornos." He loves that kind of thing. He plays this so straight.
 * Dilandau in Vision of Escaflowne
 * Misa and Teru from Death Note.
 * Baron Ashura and Count Brocken from Mazinger Z loyally followed Dr. Hell. The remainder Hell's Co-Dragons do not count because Pygman and Gorgon followed their own agendas.
 * from Prétear.
 * In Bleach, Tousen plays this to Gin's Stepford Smiler.
 * Mayuri. He's more evil than the Big Bad, commits more horrific acts and experiments than the Big Bad's Mad Scientist, and is very much a psycho. He's very likely only associated with the good guys because he gets to be the Token Evil Teammate and get paid to commit atrocities.
 * Ralph Werec from Soukou no Strain is one of these, and relies on the expectation of Mad Love as a motive; he only pretended to be in love with Vivian Medlock and to have made his Face Heel Turn for her sake. His motivations were far more scarring (in more ways than one) and left him flat-out insane, and once Captain Medlock outlives her usefulness, he turns on her too.
 * Lady Une from Gundam Wing and her not-so-hidden adoration of Magnificent Bastard Treize Khushrenada, whom she serves as his Dragon. Her pacifistic "Saint" personality is the one that is most in love with him, but her "bun and glasses" personality is exceedingly cold and ruthless.
 * Treize explains to his friend Zechs, and the audience by proxy, that Lady Une developed split personalities due to her feelings for him. She gets better, possessing a combination of "Saint"'s compassion with "Iron Une"'s competence.
 * Another Gundam example is Yazan Gable of Zeta Gundam, originally introduced as a Psycho for Hire Blood Knight. He's eventually recruited by Manipulative Bastard Paptimus Scirocco, but unlike most of Scirocco's supporters, Yazan has no illusions about Scirocco's goals and seems to be following him purely for the long green.
 * Rurouni Kenshin's Yumi Komagata and her love for the (literally) flaming Makoto Shishio.
 * At least Yumi is secure in the knowledge that, in his own twisted way, Shishio does loves her back ).
 * Villainous Crossdresser Kamatari Honjou, on the other hand, is fully aware that he'll never be loved like Yumi (because he's not a real woman) or favored like Soujirou (because he's not as good a fighter), and yet he is still obsessively loyal to Shishio to the point that Misao has to knock him out and Chou has to lie to him in order to keep him from killing himself in disgrace after he fails to carry out Shishio's last command to him.
 * And then there's Hoji who is clearly insane. He follows Shishio out of a near fanboyish belief in the latter's ability to change the world, and.
 * But he gets to go help Shishio and Yumi conquer Hell! Look how happy he is when Shishio asks if he's coming!
 * In Trigun Dominique the Cyclops seems to be following Legato like this, just as Legato follows Knives (which is far more obvious in the manga than the anime). Knives isn't exactly sane either, though.
 * Dominique never gets much character development. Legato, though...even the comparatively sane anime version of him is, in fact, fucking nuts, and this is presumably most of the reason he's so dedicated to helping Knives Kill All Humans.
 * Roberto from Monster, in a thoroughly creepy fashion.
 * In Code Geass, Diethard Reid, a TV producer who joins La Résistance not because he agrees with them, but because they're epic. Rolo and V.V. -- murderous Yandere—count, too.
 * Now now, lets be fair. Diethard was also bored at the time.
 * As Diethard explains in the second season, he hates the way the world has gotten and simply wants it to change,
 * For a more literal interpretation of "Psycho Supporter": Amamiya Yuuhi of The Lucifer and Biscuit Hammer instantly pledges his complete loyalty to Princess Sami after she vows to stop the mages' plot to destroy the world so that she can do so herself with her own fists.
 * Although after fighting the mage's golems, befriending his fellow beast knights, and coming to truly love both Sami and the world, he
 * Mahou Sensei Negima has Dark Action Girl Tsukuyomi, though she doesn't seem actually devoted to Fate himself: she seems to be following him solely so she'll have an opportunity to kill people. Oh, and have her way with Setsuna...
 * It might just be both!
 * Ni Jieni in Saiyuki. Interesting in that he is both a Psycho Supporter of Gyokumen.
 * Arguable since it's very possible that Ni Jieni is the one manipulating Gyokumen.
 * At any rate, just using her. He's psycho, and he's backing her up, but his psychosis doesn't instill loyalty or associate him with her cause.
 * from Hunter X Hunter.
 * It's especially funny because what he melts down about is that he almost just killed the girl to get her out of the way, before realizing that if she died his king could never beat her, never get over her, and never forget about her, and it would be the worst thing he could do. Therefore suicide pact with himself and screaming while he plays the violin.
 * The other two Royal Guards are comparatively sane, though they have basically the same worldview. They're just...a lot more matter-of-fact and less romantic about it. Although when Pitou was on the ground in front of Gon, begging to be allowed to save the life of the blind girl who was "of importance to one who is of importance to me" before Gon proceeded with the revenge killing attempt, that was pretty...impressive.
 * Yuno from Mirai Nikki.
 * As well as Akise.
 * While there are plenty of zealots in Hellsing 'verse, the Iscariots are prepared to commit any sin in the service of the Lord.. because their ultimate goal is to continue the fight in Hell.
 * Excel from Excel Saga is a psycho supporter of Lord Il Palazzo. Il Palazzo may be using mind control to gain supporters, but Excel is the only one who acts unhinged around him. She also uses the Subordinate Excuse to hang around him.
 * Michiko of Texhnolyze is a seemingly quiet secretary/driver for Onishi. Then we see her collecting the Texhnolyze parts, many of which are still attached to living people...
 * Oddly, some of Shibuya Yuri's most avid followers in Kyou Kara Maou are open to this accusation; i.e. following someone because of your own insanity rather than the merits of their position. Yuri's a Demon King, but his goals involve "world peace through people not fighting any more," "not doing his own paperwork" and "playing baseball."
 * Gunter—apparently actually an extremely competent academic, highly skilled swordsman, and powerful majutsusha, despite coming off as a brain-damaged Shotacon Squishy Wizard. Being around Yuri just makes him dopey as hell, but also means he intently supports whatever Yuri wants, even when it's counter to every custom of the land.
 * Conrad—almost as hypercompetent as he seems, and in fact a decent guy, but insane. Hard to say whether that first comes through when he tells Yuri that if Yuri gets killed Conrad will 'see him again soon' or when he is firm that to protect Yuri he will kill absolutely anyone, but that's just in the first dozen episodes, and by the end the level of his lifelong codependency issues have been thoroughly plumbed.
 * He doesn't really believe in this peace thing, but he believes in Yuri. Because it's Yuri. And Yuri is the center of his universe. Because someone has to be.
 * Wolfram—well, okay, he's just an eighty-four-year-old teenager in love. Pass.
 * Hube—his The Atoner thing seems weirdly noble and is totally crazy, especially with the Death Seeker element. Especially crazy when you find out that the sin he was banished for was being a gung-ho commander during the last war and being careless with the troops. Which people don't even hold against him because of all the soldiers who died, they hate him because the blind White Magician Girl everyone loved knowingly worked herself to death trying to heal his casualties. So he's basically a scapegoat for the whole ruling class' guilt about everything that went wrong in that effed-up war. And then he follows Yuuri with dedication for not entirely buying into that, even though he still does.
 * Eyeshield 21: Hiromi Kisiragi of the Hakushuu Dinosaurs is a Weak but Skilled cornerback who is absolutely dedicated in his support of team leader Marco and centre Gaou. He is also very quietly insane, preaching a Blood Knight Fighting Narcissist philosophy that claims only strength is beautiful. This stems from his past as a weak, bullied chump, and plays directly into his support of Gaou and Marco.
 * Eyeshield 21: Hiromi Kisiragi of the Hakushuu Dinosaurs is a Weak but Skilled cornerback who is absolutely dedicated in his support of team leader Marco and centre Gaou. He is also very quietly insane, preaching a Blood Knight Fighting Narcissist philosophy that claims only strength is beautiful. This stems from his past as a weak, bullied chump, and plays directly into his support of Gaou and Marco.

Comic Books

 * Some comics have played with the idea that Harley Quinn of Batman was at least slightly cracked before she met The Joker and that he simply unleashed her inner crazy, or that she'd still be just as nuts were he out of the picture...
 * Glory to the chaos king in The Incredible Hercules

Film

 * The Dark Knight Saga incarnation of the Joker's various minions have a healthy proportion of madmen among their numbers, who follow him because of his own crazed will.
 * The photojournalist played by Dennis Hopper in Apocalypse Now.
 * Repo! The Genetic Opera has the three Largo children for their father Rotti, and later, In both cases, the leader isn't really outright evil until you take into account that not only do they turn a blind eye to the activities of their supporters, they actively enable them. Pavi Largo is the creepiest example of this; he seems fairly well adjusted as far as scarred sex addicts go until the crazy comes out to play.
 * Shooter McGavin is more than happy to use his borderline stalker as a weapon against Happy Gilmore, up to and including, so long as he can get away from him as fast as possible afterwards.
 * Implied with Le Fou in Beauty and the Beast. Not only does he continue to follow Gaston and like him despite being treated like trash, but the literal translation of his name is "Insanity."

Literature

 * Bellatrix Lestrange, in Harry Potter. Word of God states that "her true love was always Voldemort," but he had no discernible affection for her, merely using her loyalty.
 * The Vengeance in A Tale of Two Cities

Live Action TV

 * Beautifully subverted on an episode of Shark, when
 * Connor on Season 4 of Angel, regarding his loyalty to Jasmine.
 * With maybe an unhealthy dose of Papa Wolf thrown in for good measure.
 * A Season 5 episode of Smallville, called "Fanatic," features one of Lex Luthor's political campaign supporters going berserk and trying to kill his opponent.

Professional Wrestling

 * Jon Heidenreich was like this to Booker T who "showed him the light" in the form of a steel folding chair to his skull. Jon then moved onto Road Warrior Animal.
 * Mickie James, until she realized her obsession with Trish Stratus was unhealthy and mellowed out.
 * Rosa Mendes to Beth Phoenix.
 * Steven Richards was like this to Victoria, even as the latter got Bored with Insanity.
 * The Basham Brothers to Shaniqua, who was the "center of their universe".
 * Eugene to Triple H.

Theater

 * Mrs. Lovett, the female lead of Sweeney Todd: The Demon Barber of Fleet Street. Spurred on by obsessive (unrequited) love for the title character, she shelters him despite his tendency towards psychopathic murder and comes up with the plan of disposing of the corpses he produces by baking them into meat pies and selling them, to her great satisfaction, for a tidy profit.

Video Games

 * Skies of Arcadia: Ramirez, Ramirez, Ramirez.
 * Subverted in Mega Man X 4: Colonel was motivated by pride when he followed General who led Repliforce on a non-violent secession from humanity after being labeled Mavericks due to a tragedy where Repliforce weapons were used. . The fact that Repliforce was "the most powerful army in history" and wasn't leaving their weapons behind for the secession didn't gel too well with the powers that be.
 * Actually, Colonel may fall under Too Dumb to Live. See, the entire conflict started when Colonel refuses to surrender and come in for questioning so an investigation as to why Repliforce robots were seen at Sky Lagoon (which had been crashed into a city by Mavericks, leading to untold amounts of devastation). The reason this is Too Dumb to Live is because X/Zero flat-out state to him (not an exaggeration; I cannot stress enough that it is said to his face) that if he does not come in, the officials will have no choice but to assume Repliforce crashed Sky Lagoon and declare them Mavericks. And Colonel states that his pride is more important, leading to his death, his sister's death, his army's death, and his leader's death. Great going, Colonel.
 * Used straight in Mega Man X 5: Our introduction to Dynamo has him begging Sigma to be allowed to let an orbiting colony crash to Earth, so he can draw out the top Maverick Hunters for a fight. As far as we know, that is his only excuse for teaming up with Sigma (he doesn't even show up in Sigma's fortress at the end, like the ally/patsy typically does).
 * Nouhime in Sengoku Basara is an example of this. She is unquestionably loyal to her husband Oda Nobunaga, but the said husband pretty much didn't care, just enjoying being the Big Bad.
 * In the third game, Ishida Mitsunari was this for Hideyoshi, despite not showing up in the second game. Upon his lord's defeat he goes on an Ax Crazy Roaring Rampage of Revenge against Tokugawa Ieyasu. Mitsunari all but worships the man as a god.
 * Strega member Jin, from Persona 3.
 * Hell,  is right there too.
 * Xenobia from Lunar Silver Star Story Complete.
 * Caina from Wild Arms 2.
 * Kefka in the first half of Final Fantasy VI. Unfortunately for his boss, Emporer Gestahl, he proves to be a little bit too psycho.
 * Pellegri to Margulis in Xenosaga, though she occasionally proves more conscienable than he is. Still, the crazy is strong in this one, which becomes particularly apparent on Michtam.
 * In Xenogears, Ramses to Emperor Cain. He loses his marbles by the end and pulls a Kefka.
 * Albel the Wicked for roughly the first third of Star Ocean: Till the End of Time.
 * Psycho Mantis supported Liquid Snake's armed revolution... only because it meant he's allowed to kill more people
 * A subplot in Sam and Max Freelance Police Season One is Max being a fan of Hugh Bliss, the founder of the Happyology-esque religion Prismatology.
 * While he took his own share when . This can also doubles as Brainwashed and Crazy
 * Statement: You meatbags risk my wrath in failing to mention my record of emphatic support for my various masters' more sociopathic problem-solving methods. Such good times we had.
 * Colonel Sergei Vladimir is this in Resident Evil Umbrella Chronicles with regards to Ozwell E. Spencer. Spencer and his Mega Corp, Umbrella, gave Sergei a home after the collapse of the USSR, and the mentally unstable Russian is obsessed with repaying Spencer for this. He tries to hold Umbrella together long after everyone else has jumped ship, goes out of his way to cover up the corporation's mistakes, and finally transforms himself into a monster in a last-ditch effort to prevent Albert Wesker from taking over the company's remnants. As Sergei himself puts it, "All for Umbrella!" It's a motto that Sergei takes very, very seriously.

Western Animation

 * Harley Quinn from Batman: The Animated Series.
 * Princess Azula
 * Though it's kind of unclear with her whether she follows the world-conquest thing so intently because she's insane, or because she was raised to conquer the world, or because of bad genetics Zuko managed to avoid, or...anyway, she follows Ozai as much because he's her father and she wants to please him as because she's a megalomaniac. A little more megalomania and she could have offed him at a some point.
 * Maybe she would have. Once Zuko was safely dead, because even exiled he was technically first in line for the throne. But she still valued Ozai's opinion.

Truth In Television

 * Nathan Leopold
 * Lynette "Squeaky" Fromme, Sandra Good, and other members of the Manson Family (Fromme and Good are the only ones who didn't recover once away from Manson).
 * Any political or religious organization or movement is guaranteed to have some within their ranks. The only difference is how vocal they are, and how powerful they become.
 * Some sports fans are just plain nuts.
 * Columbine gunman Dylan Klebold, to Eric Harris. They were both pretty psycho, but the former especially so.