* AmericansHateTingle: Not to an extreme degree, but still notable. The franchise was relatively popular in Japan back at its day, even in midst of strong competition, and its light novel and manga still keep selling surprisingly well there after more than an entire decade, which is a true feat in the shifting light novel market. In the West, mainly in the Anglosphere, however, it never caught so much with either viewers or readers. Fault goes not only to the divisive reception that series that combine TinyTyrannicalGirl and {{Tsundere}} have always had in the Anglosphere, but also to the fact that the ''Literature/ShakuganNoShana'' fad itself was already in its twilight when the ''Aria'' anime aired, which granted it far less interest than it would have attracted years before.
* ArcFatigue: Inevitably due to the combination of ''Aria'' being a HaremSeries and a LongRunner, Kinji's relationship with Aria advanced ''very'' slowly through the years. The series seemed to be reaching its conclusion in Volume 22, as the war over the Irokane was stopped, Kanae Kanzaki was finally cleared of all crimes, and Kinji freed Aria from the Scarlet Ammo explicitly through ThePowerOfLove... but despite all of this, the WillTheyOrWontThey question became indefinitely postponed ''again'' with the presence of a new evil super-group screwing things up for Kinji and the appearance of yet another romantic rival to Aria. 15 entire volumes have passed since then.
* AudienceAlienatingPremise: While amusing in its very Japanese wackiness, the premise of a bread-and-butter HaremSeries led by a Literature/SherlockHolmes descendant (among other famous characters) is not easy to market, especially in western countries, and this a part of its lack of charm. Part of this revolves around [[UncertainAudience target audience]]: Holmesians often find the premise a frivolous cheapening of Holmes, while harem genre fans see it as an average product without anything interesting.
* SugarWiki/AwesomeMusic: The anime's [[https://hidannoaria.fandom.com/wiki/Hidan_no_Aria_Original_Soundtrack OST]] by Takumi Ozawa has [[https://www.youtube.com/playlist?list=PL71E03C201444830D quite a bit of this,]] with some of the more standout examples listed below.
** The opening theme, [[https://www.youtube.com/watch?v=goB3BL3ZCCE "Scarlet Ballet"]] by May'n.
** "Hysteria Mode," the track used when Kinji activates his HSS in Episode 1.
** [[https://www.youtube.com/watch?v=MpA6xZKQJU0 The piano- and string-centric battle music,]] [[https://www.youtube.com/watch?v=wt4lgNfuX_g "Reki, Fire!"]]
** ''AA'' does not disappoint in this regard either, as indicated by [[https://www.youtube.com/watch?v=R0LSnvv-zLw its main battle theme.]]
* BizarroEpisode: The OVA. While initially a regular HotSpringsEpisode, it soon turns into a weird ghost story where time and space start unraveling while the group chases a spirit that seems to be wanting to tell them ''something''. However, none of this is clarified, as it turns out to have been AllJustADream... only the entire gang dreamed it together, and things that they learned in the dream happen to be real things they couldn't have known before. And ''then'' it turns out the ghost is real after all and is observing them. Maybe the episode's point is that there are things that not even Sherlock Holmes could understand?
* ClicheStorm: A typical complaint among reviewers, even those who liked the concept of a Literature/SherlockHolmes descendant, is that the series plays straight almost every trope related to the {{harem|Series}} genre. The latter case was even openly exploited by the producers, given that the anime shares its company, director ''and'' [[Creator/RieKugimiya lead voice]] with the original ''Literature/ShakuganNoShana'' -- but this didn't exactly help, especially because ''Aria'' was one of the last SC series to receive an anime adaptation and thus didn't have its predecessors' novelty value. (To be fair, the originality is acknowledged to improve considerably through the light novel series, but as the anime adaptation stopped just after Volume 3, people who didn't follow the novels never got to witness it.)
* CriticalBacklash: Kinji is often accused of being a VanillaProtagonist as most harem protagonists usually are. Some believe those reviews are focusing only on the superficial, as a case can be made for Kinji actually being a huge improvement over the average Yuuji Clone: unlike many of those, Kinji has his own arc which predates his relationship with Aria, enjoys a powerset both intriguing by itself and unrelated to her, is neither ObliviousToLove nor an ExtremeDoormat, and in later volumes his life stops orbiting fully around Aria; overall, a character who might have starred in their own solo series, something that can be seldom said about his homologues. However, the fact that all those aspects are not overtly emphasized, particularly in the early period of the series the anime adapts, can cause people to overlook them.
* EnsembleDarkhorse:
** Riko Mine Lupin IV is generally well-liked, even by people who aren't fans of the series, for her personality and [[LawyerFriendlyCameo implied connection to]] ''Franchise/LupinIII''.
%%** Jeanne d'Arc.
%%** G3 in later volumes.
* SugarWiki/FunnyMoments: In Episode 6, Kinji opens a drawer brought in by Shirayuki when she moved in with Kinji and Aria.
-->'''Kinji:''' Shirayuki brought these drawers here. There won't be any hazardous objects lying--\\
[''Kinji opens a drawer and gasps in shock as he discovers Shirayuki's massive collection of black and white underwear before immediately closing it'']\\
'''Kinji:''' There are... and they're hazardous to ''me''.
* GeniusBonus: The dialogue bit in which Kinji and Riko mention Aria's fighting style by name is AdaptedOut of the anime, but the viewer can reach the same conclusion as them judging by the judo throw she scores on Kinji during their scuffle at the first episode. It is [[https://en.wikipedia.org/wiki/Bartitsu Bartitsu,]] the real-life hybrid martial art of judo, jujutsu, boxing and savate used by the original Sherlock Holmes in his fight against Moriarty (though named [[https://en.wikipedia.org/wiki/Baritsu Baritsu]] in [[Creator/ArthurConanDoyle Doyle's]] books).
* HarsherInHindsight: The plot of Volume 1 of the light novel/the first five episodes of the anime -- Kinji and Aria's dealings with the Butei Killer, a [[MadBomber serial bomber]] willing to endanger innocent civilians while targeting the students of Butei High -- somehow predicted the events of the Boston Marathon bombings two years later in 2013, with both events coincidentally happening in April.
* HilariousInHindsight: [[PublicDomainCanonWelding Riko Mine is the great-granddaughter of]] Literature/ArseneLupin and her family name is a nod to Fujiko Mine of ''Franchise/LupinIII'' fame, leading to plenty of speculation as to whether or not Riko is meant to also be the child of Lupin and Fujiko. (Fujiko [[AdaptationDyeJob being depicted with blonde hair]] every now and then ''would'' help explain Riko's hair color...) Fast-forward to 2018 and ''Anime/LupinIIIPart5'', dedicating a large portion of its run to exploring [[RelationshipRevolvingDoor the relationship between Lupin and Fujiko]], reveals that [[spoiler:the pair [[RelationshipUpgrade actually wed]] (and divorced) in the interim between ''[[Anime/LupinIIITheItalianAdventure Part IV]]'' and ''Part 5''. Furthermore, the series ends with [[MaybeEverAfter the possibility]] of the pair having rekindled [[OutlawCouple their romance]], in stark contrast to [[WorkingWithTheEx how frosty the two were towards each other early on]], and their relationship is shown to still be going strong in [[Anime/LupinIIIPart6 the next series]]]]. For added hilarity, note that [[spoiler:''Part IV'' itself dealt with Lupin's attempts to annul his marriage to series newcomer (and rival thief) Rebecca Rossellini]].
* ItsShortSoItSucks: The I-U arc was solved rather quickly in the novel series, with the Professor being defeated only six volumes in (which in terms of adaptation means that, had the anime been 24 episodes long, this battle would have been its finale). Although many other storylines branch away from it due to the in-story collapse of the I-U, there are fans who believe the organization, or at least its founder, should not have been defeated so soon.
* JerkassWoobie:
** Aria. She may have treated Kinji too harshly, but her mother's been stuck in prison for Butei killings she didn't commit. It's no wonder the poor girl gets hot under the collar.
** Riko Mine. From losing her parents, to spending years as Vlad's undernourished prisoner, to being used as one of his pawns, to having her rosary (the only keepsake she has left of her mother) stolen by Vlad (who knew perfectly well how much it meant to her), to ending up being tortured by him after she tries to get it back, her life is quite the TraumaCongaLine. You can't help but feel sorry for her, despite her psycho side and initial desire to kill Aria to prove herself.
* {{Narm}}: The gurgling, growling, laughing noises that [[spoiler:Vampire!Werewolf!Vlad]] makes in the final episode of the anime make him difficult to take seriously.
* NeverLiveItDown: The fact that the lead Aria is a {{Tsundere}} voiced by Creator/RieKugimiya is pretty much the most known thing about the series.
* NightmareFuel: Riko Mine's evil laugh in Episode 4, after she "defeats" Aria.
* OlderThanTheyThink:
** The series is not the first TinyTyrannicalGirl and {{Tsundere}} light novel to feature a Holmesian female lead and a Japanese male lead with military training. That would be ''Literature/{{Gosick}}'', which started being published in 2003 (it was the earliest major SC, in fact) and whose anime adaptation premiered mere months before ''Aria'''s.
** In 2010, only one year before the ''Aria'' anime aired, Creator/JCStaff also produced ''Anime/TanteiOperaMilkyHolmes'', another anime about a female Holmes in a modern setting that features superhuman abilities (as well as a Literature/ArseneLupin character). The same year also saw the premiere of ''Series/{{Sherlock}}'', a TV series about a modern day Holmes getting entangled with terrorism. Interestingly, given that the ''Aria'' light novel was published in 2008, the trope also works in reverse towards those works; in fact, although ''Milky Holmes'' was canonically inspired by ''Manga/CaseClosed'' and ''Anime/GalaxyAngel'', the novel's popularity might have still contributed to its success.
* {{Sequelitis}}: Spin-off example, though not completely unrelated. ''Aria the Scarlet Ammo AA'' was much less successful than the main series due to a myriad of reasons: its characters were substantially less colourful, its plot was more a SliceOfLife compared to the central ''Aria'' arcs, it came a significant four whole years after the main show, and ultimately -- to put it simply -- it was not what the fandom wanted. When a new ''Aria'' anime project was announced in 2015, people were excited that they were finally continuing the series, only to find out it was actually an adaptation of a less known spin-off without any weight in the central storyline.
* SpiritualAdaptation:
** A series about an ordinary guy with a hyper-competent counter-terrorist SplitPersonality, gained thanks to his family line, who gets involved (in more than one way) with a twin-tailed, pinkish-haired Japanese prodigy agent around his own age, who keeps a persistent BettyAndVeronica situation with another female friend of the main character, all while they work for an organization of juvenile agents? With all those premises, ''Aria'' could be perfectly considered the light novel adaptation of Creator/PeterDavid's comic book series ''ComicBook/SpyBoy''. Even if the latter is relatively obscure, the similarities are so strong that it would be shocking that Chugaku Akamatsu didn't know about it.
** ''Aria'' itself later gained its own successor in ''Literature/StrikeTheBlood'', another light novel about a high school student with bloodline powers awakened by sexual arousal who fights along an armed {{Tsundere}} with abusive tendencies and attends a school located at an artificial island in Japan, where vampires and superhuman maidens live.
* TheyWastedAPerfectlyGoodCharacter: The Professor ([[spoiler:Sherlock Holmes]]) and I-U are defeated as early as the sixth volume. Given the Professor's relation to Aria's personal arc and how he was in many senses the entire series' ultimate antagonist, it is pretty easy to think he could have been saved for more action.
* TheyWastedAPerfectlyGoodPlot:
** Many reviews point out that a series about a Sherlock Holmes female descendant paired with a male student with a badass SplitPersonality, in a juvenile police-mercenary school and among descendants of [[PublicDomainCharacter some other famous characters]], sounds pretty awesome on paper. In this case, sadly, said premise was mostly spent in trite harem shenanigans led by a questionable light novel stereotype, all of which admittedly has its own audience, but is nowhere near how good it could have been.
** [[FamousAncestor Kinji's own descent from a legendary character]] (in this case, [[https://en.wikipedia.org/wiki/Toyama_Kagemoto Kinshiro Tohyama]]) is evident yet at the same time never stated, unlike everybody else's lineage. It is unknown whether this will change in the series' future.
** The Hysteria Savant Syndrome itself is an interesting idea, so much that some people believe it might have been a good premise for even an entire anime series. However, it is never explored too much. Later volumes of the light novel series delve deeper on it, but still not to a great extent.
* ViewerGenderConfusion: [[spoiler:By Volume 4, we get introduced to a girl named Kana... who is actually Kinji's long dead brother, who crossdresses so he can activate Hysteria Mode at will.]]
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