History YMMV / ACertainMagicalIndex

* EnsembleDarkhorse: [[{{Tsundere}} Mikoto]], [[IceQueen Kaori]], [[PsychoLesbian Kuroko]] and [[spoiler:[[ShyBlueHairedGirl Itsuwa]]]] are very popular with the fans, [[BreakoutCharacter ultimately spawning]] [[Manga/ACertainScientificRailgun a franchise of their own]].
** [[spoiler:[[FourGirlEnsemble Team ITEM and New Light]]]] are very popular among fans despite both groups being [[spoiler:the antagonists]].
*** Creator/KazumaKamachi noted in the afterward of NT 12 that to him, [[spoiler:Frenda Seivelun]] was just a one-shot character to be unceremoniously killed, and did not anticipate that she would be so popular to the fans. This led to her getting a big role in Railgun and to her becoming a major plot point in NT 6 and 12 despite being long dead.
** Now with the second season of Index, Fukiyose Seiri has become very popular with fans on her debut in Episode 8.
** Accelerator has a ''huge'' fanbase due to how AxCrazy awesome he is, to the point that a large amount of fans claim HE should be the main character, not Touma.

* FanPreferredCouple: Majority of the fans who don't [[MarryThemAll ship every and all girls with Touma]] (which is a significant portion in and of itself) ship him with Misaka. Though after NT 9, a big but lesser part of the fanbase has started shipping Touma with Othinus.

* TheChrisCarterEffect: A frequent phenomenon among fans. The series has by now introduced [[LoadsAndLoadsOfCharacters so many plot-relevant characters]] with [[AlwaysABiggerFish even more potent powers]] with their own storylines that many people have trouble keeping up even with character charts. Combine this with the fact that the revelations about Imagine Breaker and the way Espers work have been minimal so far (and many other less important questions haven't been answered either, but [[KudzuPlot rather just raise new questions]]) and that CharacterDevelopment has been all but non-existent for the majority of characters as of late (including main character Touma), and that the staff seems to be more interested in working on the spin-offs rather than the main story, and you have a giant chaos that has little potential of eventually wrapping itself up completely.

** Kakine Teitoku a.k.a. Dark Matter and Uiharu Kazari. Yes. That Uiharu. [[WouldHitAGirl Despite their first interaction with each other is a]] [[IncrediblyLamePun bone-chilling]] one, that didn't stop certain amount of fans from wearing their ShippingGoggles.

* FriendlyFandom: The fandom is on relatively good terms with some other fandoms.

** Academy City's Power Curriculum Program. In theory anyone undergoing this program can become an Esper yet there are still people who have yet to gain powers and even those who did never go a higher level which suggest the program has some problems. [[spoiler:However Vol. 22 reveals the program is secretly being undermined by the Higher Ups of Academy City who decide who can and cannot gain Esper powers and/or go a higher level based on the type of the powers that person has. This revelation makes it much worse once you realize Level 0's like Saten, the Skill Outs gangs and low level espers like the Level Upper users, who work hard to gain powers/higher levels but never can because their training is being sabotaged as the Higher Ups see no point of helping anyone who doesn't have the powers they want. That's right, the city is responsible of destroying the dreams of many students and leading them into path of cynicism and crime. Particularly harsh since the Program prevents anyone who goes through it form learning magic, even if they don't get anything out of it.]]

* MagnificentBastard
** Aleister Crowley

** Mikoto and Mikasa, carrying over from [[Manga/ACertainScientificRailgun the spin-off it got started in.]]

** Academy City's Power Curriculum Program. In theory anyone undergoing this program can become an Esper yet there are still people who have yet to gain powers and even those who did never go a higher level which suggest the program has some problems. [[spoiler:However Vol. 22 reveals the program is secretly being undermined by the Higher Ups of Academy City who decide who can and cannot gain Esper powers and/or go a higher level based on the type of the powers that person has. This revelation makes it much worse once you realize Level 0's like Saten, the Skill Outs gangs and low level espers like the Level Upper users, who work hard to gain powers/higher levels but never can because their training is being sabotaged as the Higher Ups see no point of helping anyone who doesn't have the powers they want. That's right, the city is responsible of destroying the dreams of many students and leading them into path of cynicism and crime.]]

** Kakine Teitoku a.k.a. Dark Matter and Uiharu Kazari. Yes. That Uiharu. [[WouldHitAGirl Despite their first interaction with each other is a]] [[IncrediblyLamePun bone-chilling]] one, that didn't stop the fans from wearing their ShippingGoggles.

* FoeYayShipping: Touma and pretty much all of his female opponents, be they the ones who actually do grow feelings for him (such as Kanzaki, Agnese, Lessar, and Othinus), the ones who have flirty moments vague or overt (such as Oriana or Carissa), or even those who don't have any such feelings (such as Shelly or Vento). And then there's whatever [[HoYay Thor's got going on]]...

* LauncherOfAThousandShips: The three primary characters, [[TheHero Touma]], [[AxCrazy Accelerator]], and [[ButtMonkey Shiage]], have all gained their own UnwantedHarem as the volumes moved along. Touma in particular has been shipped with pretty much ''every'' female character at least once, including members of Accelerator and Shiage's harems.

*** [[TheHero Touma]] and [[TeamNormal Saten]] get paired in a surprising amount in fanfics, despite the fact that they've only met face-to-face when he borrowed her good luck charm for the Daihasei Borrowing Race. Probably because they're both normal (mostly) and that Saten's protection charm actually managed to negate Touma's bad luck for once.

** [[{{Main/Teleportation}} Teleportation Kuroko Shirai hanging out with her friends and immediately excuses herself by using teleportation]] to glomp Misaka.

* TheyWastedAPerfectlyGoodCharacter: Accelerator suffers from this as of [[spoiler:Genesis Testament Volume 1. 40 volumes after his HeelFaceTurn, he just decides to report the entirety of Academy City's dark side to the police, and as a result ends up in prison for a very long time. Numerous fans were not too pleased with this, to the point where some claim that Accelerator being imprisoned makes his entire character arc up to that point meaningless.]]

** Aleister: Is he nothing more than a giant {{jerkass}} who loves nothing more than [[GambitPileup piling up one evil scheme after another]]? Or a WellIntentionedExtremist with ulterior motives? His actions would suggest the former, while his backstory leans in the direction of the latter. Revelations in the later light novels suggest that he is a WellIntentionedExtremist.

* LauncherOfAThousandShips: The three primary characters, [[TheHero Touma]], [[CrazyAwesome Accelerator]], and [[ButtMonkey Shiage]], have all gained their own UnwantedHarem as the volumes moved along. Touma in particular has been shipped with pretty much ''every'' female character at least once, including members of Accelerator and Shiage's harems.

** Accelerator has a ''huge'' fanbase due to how AxCrazy [[CrazyAwesome Awesome]] he is, to the point that a large amount of fans claim HE should be the main character, not Touma.

* FranchiseOriginalSin: Many were livid at Creator/JCStaff for not properly adapting ''Index III'', instead making it a CompressedAdaptation, locking out a lot of information. The thing is, JC Staff did the same thing to both ''Index I'' and ''Index 2''.[[note]]''Index I'' covered Vol. 1-6, and ''Index 2'' covered Vol. 7-13 and Vol. SS, a side novel of the series.[[/note]] The difference is, while the first two seasons cut out plenty of information, it was mostly restricted to worldbuilding and extra characterization, and the plot was perfectly understandable otherwise. However, ''Index III'' cut out actual plot-relevant action, dialogue, and characters completely. By the time ''Index III'' had begun airing (seven years after ''Index II''), plenty of fans had read the light novels and caught up to the series by that point, so now the changes that were made were much more noticable.

* FranchiseOriginalSin: Many were livid at Creator/JCStaff for not properly adapting ''Index III'', instead making it a CompressedAdaptation, locking out a lot of information. The thing is, JC Staff did the same thing to both ''Index I'' and ''Index 2''.[[note]]''Index I'' covered Vol. 1-6, and ''Index 2'' covered Vol. 7-13 and Vol. SS, a side novel of the series.[[/note]] By the time ''Index III'' had begun airing (seven years after ''Index II''), plenty of fans had read the light novels and caught up to the series by that point, so now the changes that were made were much more noticable.

* FranchiseOriginalSin: Many were livid at Creator/JCStaff for not properly adapting ''Index III'', instead making it a CompressedAdaptation, locking out a lot of information. The thing is, JC Staff did the same thing to both ''Index I'' and ''Index 2''.[[note]]''Index I'' covered Vol. 1-7 with a bit of 8, and ''Index 2'' covered Vol. 8-13 and Vol. SS, a side novel of the series.[[/note]] By the time ''Index III'' had begun airing (seven years after ''Index II''), plenty of fans had read the light novels and caught up to the series by that point, so now the changes that were made were much more noticable.

** A big reason for [[spoiler:Princess Carissa's ''coup d'etat'' against her mother]] in Volumes 17 & 18 is that she believes the United Kingdom has become too stifled by the European Union and having its rights infringed upon with impunity by a corrupt alliance deep in the Roman Catholic Church's pockets, and wants to break free of it by force. In June 2016, the real United Kingdom has voted by referendum to leave the European Union.