History AllThereInTheManual / AnimeAndManga

* In ''Manga/DeathNote'', you never do find out L's real name. Unless, of course, you get the book with all the supplemental information in it or watch the [[Film/LChangeTheWorld live action film ''L: Change the WorLd]]. It's [[spoiler:L Lawliet]].

* Some information in ''Manga/{{Naruto}}'' can only be found in databooks. Most of the Tailed Beasts and the names of the other Jinchuuriki and Kages were shown in the supplementary materials long before they were revealed in the actual manga.

* Want to know the {{backstory}} for ''Anime/OnePieceFilmStrongWorld''[='=]s villain, Gold Lion Shiki? You have to either go read the supplemental "Chapter 0" or watch the OVA based on said chapter.

* Any character in ''Webcomic/AxisPowersHetalia'' that might come across as a FlatCharacter probably has most of his/her personality only displayed in the profiles. Some characters can only be seen in the author's blog.
** There's also a lot of references to past events that you might not understand without either pausing to read the history annotations or looking it up. Then again, pretty much everything in that show is related to past events, even Chibitalia's dress.
** Himaruya had a habit of this with his earlier series as well. Many characters in ''Manga/SusumeKitakouHousoubu'' and ''Barjona Bombers'' were never really fleshed out or even got to ''appear'' in the series, although illustrations and (lost) profiles served to provide information on them.

* Like many {{Light Novel}}s [[AnimatedAdaptation adapted into anime]], ''LightNovel/HaiyoreNyarkoSan'' loses some information in the transition, some of it quite relevant. The most pertinent example comes in episode 2, where Mahiro realizes that Nodens' base is BiggerOnTheInside, which just passes with a remark from Nyarko about how well he's handling such an unusual situation; in the light novels, it's revealed that he possesses the ability to perceive and [[RippleEffectProofMemory be unaffected by distortions in space-time]], which becomes a major ChekhovsSkill later on when [[spoiler:an evil former classmate [[RetGone wipes Nyarko and Cuko from existence]] and Mahiro is the only person who remembers they ever existed.]]

* In ''Anime/MaiHime'', the sound dramas, specials (often characters narrating about themselves) and art books often provide more information about the characters, and the short story "Natsuki no Prelude" contains details about how Natsuki became a [=HiME=] and her friendship with Shizuru.
* Similarly, the ''Anime/MaiOtome'' sound dramas provide bits of backstory from the main series, such as how Tomoe met Shizuru, some of Yukariko's backstory (she was a Meister who had to cancel contracts due to her masters falling in love with her) and Mai and Natsuki's early days at the academy, including how Natsuki became Shizuru's room attendant.

* Want to know the {{backstory}} for ''Anime/Anime/OnePieceFilmStrongWorld''[='=]s villain, Gold Lion Shiki? You have to either go read the supplemental "Chapter 0" or watch the OVA based on said chapter.

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* ''Anime/TheIdolmaster'' - Some events in the anime series make a lot more sense if you've played through the game it's based on and unlocked the backstories for the idols.

** The ''Renewal of Evangelion'' DVD contains the director's cut editions of episodes 21-24. New footage was added in order to make the plot more comprehensible and answer a few lingering questions (such as Kaworu's origin and (some of) the circumstances behind the war with the Angels).

** Played straight in episode 11: not an actual manual per se, but walls of the crawlspace inside the Magi supercomputer units are covered with pages of codes, schematics, and other notes left by Dr. Naoko Akagi, the system's developer (along with a TakeThat aimed at Gendo). Maya says that with those notes, it'll be much easier to reprogram the Magi.

* The ''Manga/BirdyTheMighty'' OVA series had a couple of audio drama CDs released to help flesh out the universe.

* ''Manga/TheFiveStarStories'' by Mamoru Nagano contains some of the most ambitious worldbuilding in anime and manga history, a lot of which gets little exposure in the series proper. Fortunately, the English editions come with sections from the sourcebooks printed in the back of each issue, including full-colour illustrations.

* For an example of a series where ''all'' the materials are becoming officially translated for the West, see ''Anime/DotHackSign'' and [[Franchise/DotHack its sequels]] -- to get the full story, you need to read a novel, watch a [[Anime/DotHackSign 26 episode anime series]], play four games, watch the four OVA anime episodes bundle one with each game, read four more novels, and read a three volume manga (and/or watch the 12 episode anime adapted from it, but that isn't canon so it won't really help you), preferably in that order. That's not counting the non-canon spinoffs or the sequel project, which consists of much the same combination again.
** The 3 ''.Hack//GU'' games, in fact, took place after the 26 episode series ''.Hack//Roots'', directly continuing the story of the protagonist Haseo. However, the first ''GU'' game was released several months before the first DVD of ''Roots'' was translated and released. Therefore, gamers who had not been watching fansubs of Roots were completely in the dark about who Shino was, what had happened to her, and why Haseo was going so mental over her; especially since the game was purposefully vague on details.
*** There's going to be a third project that takes place in the real world too.
*** On the other hand, watching the anime first will completely spoil most of the plot, especially one particularly dramatic twist that occurs at the end of the second game. So it's not really clear what order these were meant to be seen in.
** Not everything has made it to the west. ''.hack//Zero'' still hasn't been translated. Seeing as it was set in The World R:1 and they've moved on past R:2 to R:X, it's doubtful it will see light of day. Or be finished in Japan for that matter.

* Similarly, the ''Anime/MaiOtome'' sound dramas provide bits of backstory from the main series, such as how Tomoe met Shizuru, some of Yukariko's backstory (she was a Meister who had to cancel contracts due to her masters falling in love with her) and Mai and Natsuki's early days at the academy, including how Natsuki became Shizuru's room attendant.
* Much of the back stories and family life for ''Anime/RoninWarriors'' in ''Yoroiden Samurai Troopers'' can only be found in supplemental books and Drama [=CDs=].
* A lot of additional information for the ''Anime/TigerAndBunny'' series shows up in the audio dramas (which are included with the Blu-Ray releases) or in supplemental guides. Information within them ranges from [[FandomNod amusing tidbits]] (such as all the heroes' first crushes) to more plot-relevant elaborations (like who Kotetsu's wife was and how he met her).
* In ''Anime/FutureGPXCyberFormula'', there are several drama [=CDs=] and supplemental artbooks that details the backstories about the characters, such as in the last drama CD, which revealed Kaga's backstory, how Kaga got his scar on his forehead and why he warned Hayato about the Zero Realm in ''ZERO'' [[spoiler: (he was in a racing accident with his best friend Eiji which was caused by the Zero Realm and Eiji was killed)]].
* ''Anime/TheIdolmaster'' - Some events in the anime series make a lot more sense if you've played through the game it's based on and unlocked the backstories for the idols.
* Supplemental materials for ''Anime/GhostInTheShellStandAloneComplex'' have very detailed information about the world of the show, including the political backdrop of the story (which is only hinted at in-series) as well as plenty of weapon descriptions.
* In ''Anime/GirlsUndPanzer'', a fair amount of information can be found in the spinoff materials
** The OVA series sheds light on how the school ships work.
** The manga shows the battle against Anzio, which took place offscreen in the anime, in its entirety.
** The ''Little Army'' manga has two fairly significant revelations - that Miho actually enjoyed tankery while she was young (struggling to find people with whom she could do it, and a reason to do it) and that [[AloofBigSister Maho]] [[spoiler:loves Miho and wants her to find her own way of tankery]].
** A lot of details of the setting, such as actual rules of Tankery (like how only prototypes and production models made prior to the end of World War II are allowed) and world history, are only found in supplementary materials, and never mentioned in-show. The Blue-Ray supplements also mention the existence of "Unlimited" Tankery. Primarily practiced in America, in contrast to "traditional" Tankery followed in such places as Japan, Britain and France, "Unlimited" Tankery dispenses with the many mechanical limitations imposed in the traditional rules, and allows absurd levels of customization, such as removing tank armor and installing 12-cylinder engines, to the point that the tanks in questions look like anything but tanks. This particular discipline was also a source of controversy within the global Tankery Federation.
* ''Manga/AttackOnTitan'': At the end of certain chapters, an extra page goes into detail on certain aspects of the world. Examples include a roughly to scale picture of the Walls and how much area they protect and details of humanity's technology. The anime incorporates this information by displaying it during its [[EyeCatch Eye Catches]].
* ''Anime/SenkiZesshouSymphogear'' often has large amounts of information about the mechanics of the Symphogears and Noise hidden away in keywords (such as the Symphogear system having over 3,000,000 limiters as well as how the sync ratio-enhancing drug [=LiNKER=] works), and it also detailed [[GenkiGirl Hibiki's]] DarkAndTroubledPast and DisappearedDad before those issues came to the forefront in the third season, GX.
* In ''Anime/CuteHighEarthDefenseClubLove'', this is downplayed with Tazawa's first name (Masuya), as Tazawa only comes into the story at episode 5 of 12, season 1. The online manga plays this straight regarding some of the villainous trio backstory (e.g. how Kinshiro and Arima met) but the final chapter, found in the print version only, has to be understood by watching the canon material.
* Like many {{Light Novel}}s [[AnimatedAdaptation adapted into anime]], ''LightNovel/HaiyoreNyarkoSan'' loses some information in the transition, some of it quite relevant. The most pertinent example comes in episode 2, where Mahiro realizes that Nodens' base is BiggerOnTheInside, which just passes with a remark from Nyarko about how well he's handling such an unusual situation; in the light novels, it's revealed that he possesses the ability to perceive and [[RippleEffectProofMemory be unaffected by distortions in space-time]], which becomes a major ChekhovsSkill later on when [[spoiler:an evil former classmate [[RetGone wipes Nyarko and Cuko from existence]] and Mahiro is the only person who remembers they ever existed.]]
* ''Manga/CityHunter'': The volume edition of the manga includes various informations missing from the manga chapters, ranging from backstage data to how Ryo succeeded in ''spending one hundred million yen in a week'' ([[spoiler:a donation to a clinic specialized in rehabilitating drug addicts, where he had just sent a big group of girls that Union Teope had enslaved with drug addiction]]).
* In ''Manga/BlackClover'' there are some details about the characters that one reading only the chapters (and not even the character information shown between chapters in the volumes) would not get to see, such as a character's age or full name. Done once again with the official guidebook, which lists more details about the characters, including minor characters.

* ''Manga/TheFiveStarStories'' by Mamoru Nagano contains some of the most ambitious worldbuilding in anime and manga history, a lot of which gets little exposure in the series proper. Fortunately, the English editions come with sections from the sourcebooks printed in the back of each issue, including full-colour illustrations.
* ''VideoGame/DevilMayCry [[Anime/DevilMayCryTheAnimatedSeries The Animated Series]]'' doesn't bother to fully explain Dante's connection to Trish or Lady, their respective histories being found in the first and third game. Amongst others.
** The series are meant to be viewed in the order of Games 3, 1, the anime, 4, and 2. So missing the games does indeed leave you with a lot of unanswered questions when it comes to the anime series.
* ''Manga/CromartieHighSchool'' just flat out tells you that if you want to know certain things about the show, read the manga. Of course, it is [[GagSeries that kind of show]], after all.
* The hosts for Papillon's homunculi in ''Manga/BusoRenkin'' were all humans that pissed him off for one reason or another, as detailed in their character bios in the tankobons. Good luck understanding Papillon's hallucination without reading the bios first.
* The entire ''VideoGame/{{Gungrave}}'' anime isn't just a prequel, it's The Old Testament Bible of the video game's history. Unfortunately, many game fans were be bewildered by [[GenreShift the complete change of narrative from the action-based medium]], and many who would appreciate it for its own merits were put off by an over-the-top zombie shoot-em-up the show began with.
** The artbooks provide a lot background info as well.
* Any character in ''Webcomic/AxisPowersHetalia'' that might come across as a FlatCharacter probably has most of his/her personality only displayed in the profiles. Some characters can only be seen in the author's blog.
** There's also a lot of references to past events that you might not understand without either pausing to read the history annotations or looking it up. Then again, pretty much everything in that show is related to past events, even Chibitalia's dress.
** Himaruya had a habit of this with his earlier series as well. Many characters in ''Manga/SusumeKitakouHousoubu'' and ''Barjona Bombers'' were never really fleshed out or even got to ''appear'' in the series, although illustrations and (lost) profiles served to provide information on them.
* ''LightNovel/{{Baccano}}'': Generally, the anime is relatively self-contained and understandable without turning to the LightNovels (sans one scene in episode one that is LeftHanging), but there's obviously a lot of background that doesn't find it's way in, and there's also quite a bit that goes on ''after'' the events in the anime. [[NoExportForYou Good luck finding translations, though]].
* The canon of ''Anime/WeissKreuz'' is distributed across two anime series and an OAV, a good many drama [=CDs=], and several manga and short stories. Fortunately the first anime series is pretty well self-contained, but in the absence of the material from the OAV and drama [=CDs=] the drastic changes between it and sequel series ''Weiss Kreuz Gluhen'' make no sense at all. Naturally, [[NoExportForYou only the two anime series have been officially released to western audiences]].
* In the American release of the ''Anime/ReadOrDie'' OVA, the post-it notes in Yomiko's apartment are mistranslated because the translators apparently didn't realize "Nenene" was a name; she doesn't show up in the OVA but in the manga and subsequent TV series, Sumiregawa Nenene is Yomiko's best friend.
* In ''Manga/DeathNote'', you never do find out L's real name. Unless, of course, you get the book with all the supplemental information in it or watch the [[Film/LChangeTheWorld live action film ''L: Change the WorLd]]. It's [[spoiler:L Lawliet]].
** We also find out that Misa [[spoiler:committed [[DrivenToSuicide suicide]].]]
** The manga mentions that [[MemeticMutation they were barbequed potato chips.]] It's actually a relevant plot point because it ensures [[CrazyPrepared no one will discover that little set up]], as no one else in his family will touch that flavor.
* The ''VideoGame/SakuraWars'' {{OAV}}s and [[Anime/SakuraWarsTheMovie movie]] are based on (and mostly continuations of) the games. Somehow America got the former without the latter.
* Random splash pages in ''Manga/FairyTail'' will be entirely dedicated to a member of the titular guild. When it's a main character like Erza, or a minor one with a decent amount of attention like Elfman, it will tell you random things like how Erza terrorizes fashion designers into making her armor, of that Elfman once lost a bird and never realized the one he found was not the same. If it's a background character who gets roughly one line per arc at best, it will give detail into their past and personality. Much of this information ends up getting incorporated into the anime as filler.
* Overall, the original LightNovel series of ''LightNovel/{{Slayers}}'' goes into detail of how the magic system and the like works better than the anime does, but not in clarity, as both forms of media tend to contradict themselves. The only true "manual" for the series is a long series of interviews by creator [[WordOfGod Hajime Kanzaka]], and he [[FlipFlopOfGod flops around]] and [[ShrugOfGod whimsily comes up with answers to questions]] to the point that he's making every potential canon fact up on the fly. The only truly solid facts are extended backstories of the main characters (especially important in regards to IdiotHero Gourry because he is the only major character whose background gets no spotlight in any media). Even then, some incidents, such as Gourry and [[ShrinkingViolet Sylphiel's]] first meeting and Lina's great fear of her [[AloofBigBrother older sister]] are never explained.
** Also, there are two radio dramas that act as extensions of the ''Slayers Premium'' NonSerialMovie; a prologue and an epilogue that both set the stage and tie up loose ends (including how [[spoiler:Naga sided with the BigBad of the movie and how Amelia was saved after being blown off to an abandoned island]]); naturally, they're only available in Japan. The manga adaptation as a whole does a better job at telling the story.
* Some information in ''Manga/{{Naruto}}'' can only be found in databooks. Most of the Tailed Beasts and the names of the other Jinchuuriki and Kages were shown in the supplementary materials long before they were revealed in the actual manga.
** ''Anime/TheLastNarutoTheMovie'', unlike the other films, holds relevance to the overall plot as it's events take place between the last two chapters of the manga, even being regarded as Chapter 699.5
* At the end of every ''Manga/FutureDiary'' volume, there is an {{Omake}} that may explain certain things that were not very obvious, such as how and why the 3rd, 4th and 9th were targeting each other, and how they began to focus on Yukki. It also gives a little background info on some of the other future diary holders.
** There is also ''Mosiac'' and ''Paradox'', which focus on the Ninth and Akise, giving more info on the Sixth as well.
* A few of ''Manga/ChibisanDate'''s characters only appear in the author's blog.
* ''Anime/PuellaMagiMadokaMagica'''s website gives extra information on the witches and their minions and familiars. To some extent, anything in [[CypherLanguage runes]] counts, as few viewers take the time to decode it.
** The DVD releases come with audio dramas. The first one is about the cat that appears only in the TitleSequence. The third one expands on Kyoko's past, and how she knew Mami. The second one is [[SliceOfLife probably]] [[AffectionateParody not canon]].
** ''VideoGame/PuellaMagiMadokaMagicaPortable'' has even more witches, particularly [[spoiler:the witch forms of Mami, Kyoko and Homura]]. Eventually, the latter witch appeared in Rebellion, the movie sequel to the anime, bringing it out of this territory, but the other two still have yet to make an appearance in the main series.
* In ''Anime/MaiHime'', the sound dramas, specials (often characters narrating about themselves) and art books often provide more information about the characters, and the short story "Natsuki no Prelude" contains details about how Natsuki became a [=HiME=] and her friendship with Shizuru.

* The incidents between the ''Anime/MartianSuccessorNadesico'' TV series and movie were explained in various Japanese-only video games, novels, and radio shows, leaving American fans puzzled at the movie's very different tone.
* The ''Mazinger'' franchise (''Anime/MazingerZ'', ''Anime/GreatMazinger'', ''Anime/UFORoboGrendizer'', ''Anime/GodMazinger'', ''Manga/NewMazinger'', ''Anime/{{Mazinkaiser}}'', ''Manga/MazingerAngels'', ''Anime/ShinMazinger'', ''Manga/ShinMazingerZero''...) has seen released supplementary manuals and books (such like the ''Mazinbible'') providing with additional information and backstory about the series and the worlds where they happen, their characters, blueprints of mechas and bases...
* The difference between ''VideoGame/{{Gatekeepers}}'' and ''Anime/GateKeepers21'' is staggering, due to novels and a video game.
* The anime ''Doomed Megalopolis'' features a confusing narrative quite difficult to follow for those who have not acquainted themselves with the cultural references or the source material ''Literature/TeitoMonogatari''. This is partly because the anime adapts only the first 1/3rd of the novel and tries to force in a conclusion to make up for it's lack of completeness.
* A large amount of key information useful in understanding the story can only be found in the supplemental materials for ''Anime/NeonGenesisEvangelion'':
** Essentially the only way to even ''try'' to make sense of ''NGE'''s plot is to look at the "classified files" in the spin-off game for the UsefulNotes/PlayStation2, which was coincidentally [[NoExportForYou never released in the States]].
** There was actually another manual that was released later, then basically overtook the previous manual in canonicity. No one had translated that into English yet. This is technically the third time it happened, since the Spin-Off Game decanonized the first manual called the ''Red Cross Book''. It's likely they'll continue making new manuals with mildly and noticeable different interpretations of what's going on until they finally go bankrupt.
*** Curiously, though the new Chronicles share many major points of info with the [=PS2=] Game, they curiously completely ignore all references to a certain group of Secret Benefactors that don't ever show up within the Anime at all. In combination with Gainax's OFFICIAL stance on the Game being that "All plot details were made specifically" for the Game, it's possible we got Retconning Manuals on our hands here.
** The ''Renewal of Evangelion'' DVD contains the director's cut editions of episodes 21-24. New footage was added in order to make the plot more comprehensible and answer a few lingering questions (such as Kaworu's origin and (some of) the circumstances behind the war with the Angels).
** Averted in the first episode: the first time Shinji comes face-to-face with Eva-01, he begins flipping through the Nerv book Misato gave him earlier, but Ritsuko says (in the Japanese version), "You won't find this in the manual."
** Played straight in episode 11: not an actual manual per se, but walls of the crawlspace inside the Magi supercomputer units are covered with pages of codes, schematics, and other notes left by Dr. Naoko Akagi, the system's developer (along with a TakeThat aimed at Gendo). Maya says that with those notes, it'll be much easier to reprogram the Magi.
* The ''Manga/KokoWaGreenwood'' OVA literally directs the viewer to a specific chapter of the manga to explain a reference. This is because the second OVA happens after the next 4 (it even refers obliquely to the plot of 5 and 6). AND it's a sequel to a story they didn't animate.

* ''Anime/{{Pokemon}}'':
** ''Anime/PokemonTheFirstMovie'' could not be fully understood without ''[[Radio/PokemonTheBirthOfMewtwo The Birth of Mewtwo]]'' CD drama to accompany it. It doesn't help that the partial animated adaptation of that CD Drama, which was basically new scenes added to the beginning of later Japanese releases of the first movie and treated as additional parts of the film, was cut out from the dub (an English adaptation was available, but only on the bilingual Japanese DVD releases). Fortunately, 4Kids later included this for American fans in the ''Anime/PokemonMewtwoReturns'' DVD.
** ''Anime/{{Pokemon 2000}}'' has two instances of this: First, the scene near the end where the collector found the Ancient Mew card on the shore in the wreck of his ship. This scene makes sense in English because they added a line earlier where he said that it was the object that started his collection. In Japanese however, you had to be lucky enough to get the program book given out at theaters. Also, that program book gives his name, which is never said in dialogue (it's Jirarudan, and his ship is called Hikoukyuu). To complicate things, in English he has two names--the captions call him Gelarden (an acceptable if not slightly convoluted Romanization of the original) while the English movie book calls him Lawrence III. As in Japanese, no name is said aloud.
** There are [[LightNovel/PocketMonstersTheAnimation two novels]] by Creator/TakeshiShudo, a major writer for the anime, that give [[http://cindysuke.tumblr.com/post/34817930237/the-facts-about-pokemon-world-lol insight into]] [[http://bmgf.bulbagarden.net/f313/world-according-takeshi-shudo-15688/ the world.]] It tells us stuff like what happened to Ash's father, Brock's siblings are only his half-siblings, and that ten-year-olds are legal adults (they can get arrested, they have to pay taxes, [[{{Squick}} they can get married...]]). A lot of the info isn't canon nowadays but it does make sense in the Kanto days, like how Officer Jenny was able to jail a bunch of kids so easily.
* In ''Anime/YuGiOh'', there are various questions in the anime that are All there In The [[Manga/YuGiOh Manga]], mostly characters' backstories.
** Still questionable though, since the anime already contradicts aspects of the manga as it is.
* ''Anime/YuGiOhArcV'' features the Four Heavenly Dragons as the main focus of the story along with their owners and the Four Bracelet Girls. The real life Original/Trading Card Game features human versions of the Four Heavenly Dragons, revealing the gender of each dragon.

* Masaki Kajishima, main writer for the ''Anime/TenchiMuyo'' OVA-[[TheVerse verse]], has regularly released supplemental material, such as novels and self-published doujinshi, with information about that continuity. One of the reasons for releasing the {{spinoff}} series ''Anime/TenchiMuyoGXP'' before the ''Tenchi'' OVA {{Revival}} series was to introduce some of the new characters and other elements from the novels to the audience that hadn't read (or wasn't able to read) them.
** Outside of the OVA series, there was a manga released around the time the ''Anime/TenchiUniverse'' GrandFinale movie ''Tenchi Forever'' was that explained a big WhatHappenedToTheMouse, namely Sasami's disappearance from the plot: [[spoiler:She ends up encountering and bonding with her universe's version of Tsunami, it's hinted that Tsunami's power is what allows Ryoko to save Tenchi and it's suggested that Sasami and Tenchi will get together.]]
* Ryo Akiyama from ''Anime/DigimonTamers'' is literally from the ''Anime/DigimonAdventure'' AlternateUniverse, and thus he and his Digimon don't follow the same rules as the rest of the cast. This is all [[AllThereInTheManual explained via the multiple video games he stars in]].
** Similarly, Ken's backstory in ''Anime/DigimonAdventure02'' has him disappearing into the Digital World as a kid and reappearing a short time after; later, we see a scene of him adventuring with another kid and getting infected by a Dark Seed. These are both references to the game where he teamed up with Ryo.
** Unfortunately, ''none'' of these games were released [[NoExportForYou outside of Asia]], so this resulted in some confusion.

* Want to know the {{backstory}} for ''Anime/Anime/OnePieceFilmStrongWorld''[='=]s villain, Gold Lion Shiki? You have to either go read the supplemental "Chapter 0" or watch the OVA based on said chapter.
** Likewise for ''Anime/OnePieceFilmZ'', where the titular villain's backstory is revealed in Volume 1000, a complementary book that was given as a present to Japanese movie-goers. However, this is actually subverted, as part of Z's backstory is mentioned in the movie itself, and the book only reveals it in full.
* The [=OVA=]s of ''Manga/{{Gravitation}}'' take place after nearly the entire manga, only obliquely hinting at its events in flashbacks; Yuki's [[DarkAndTroubledPast troubled past]] isn't even ''mentioned''.
* ''Manga/XxxHolic'' and ''Manga/TsubasaReservoirChronicle'' have ended up so interconnected that it is nigh impossible to understand one without reading the other. And even then you wish you had the option to phone Ohkawa and demand an explanation.
** It also helps if you've read all Creator/{{Clamp}}'s ''other'' manga, particularly ''Manga/CardcaptorSakura''.
** Don't even try watching the second [[OriginalVideoAnimation OVA]] without having read the manga. [[MindScrew Or having read the manga for that matter]].
* The ''AudioPlay/SaintBeast'' anime series and [=OVAs=] are more illustration than substantial, the whole story happens in the audio dramas.
* The ''Anime/KiddyGrade'' artbook contains a timeline for the main characters and the changes in attire as well.
* ''Anime/CodeGeass'' actually has quite a few forms of All There in the Manual, including Sound Episodes (released on separate [=CDs=]) as well as Picture Dramas and short story inserts with the [=DVDs=]. Unusually, Bandai localised all these into English, with the Sound Episodes being part of the LimitedSpecialCollectorsUltimateEdition package.

* ''Manga/JoJosBizarreAdventure'' has several enemy character and later Stand names just outright omitted in early story arcs. Most of the villains in ''[[Manga/JoJosBizarreAdventureStardustCrusaders Stardust Crusaders]]'' go entirely unnamed in the original publications, only to be given names later on in the volumized editions and art books. This was particularly egregious when Viz translated it into English the first time around and gave the name "Rubber Soul" to the character Steely Dan, when Rubber Soul is the name of a character that appears earlier but goes unnamed. The anime series fixes this by at least giving characters' names in eyecatchers. Later parts of the manga also give character names and Stand names either explicitly in the text, as part of a cover page, or again later in the volume versions.
** The OVA series also suffered from this, as it featured ''only'' the ''Stardust Crusaders'' plotline but began the OVA halfway through it and then from there was a pretty abridged version of the original storyline. This was rectified years later when a second OVA from the same studio released a prequel OVA series to cover the first half of ''Stardust Crusaders'', which was still extremely abridged, but at least explained what the hell led up to the first series' events. The English adaptation released all of the episodes in chronological order, and added a narrated summary of the events in ''Phantom Blood'' and ''Battle Tendency'', the first two arcs of ''[=JoJo=]''.

* While not too extreme, ''Manga/DemonSlayerKimetsuNoYaiba'' does have certain events and plot relevant information given outside of the manga pages / anime scenes proper, most of them come in the form of Extras contained within the compiled manga volumes, with the rest residing in databooks; deeper details on key events, character trivia and more background are guaranteed to be reserved for those expansions. A good example is how you will never know Mitsuri was briefly trained by Kyoujuro within the Breath of Flame, which she developed into the Breath of Love, without reading through said extras.

* The hosts for Papillon's homunculi in ''Manga/BusouRenkin'' were all humans that pissed him off for one reason or another, as detailed in their character bios in the tankobons. Good luck understanding Papillon's hallucination without reading the bios first.

* ''Manga/JoJosBizarreAdventure'' has several enemy character and later Stand names just outright omitted in early story arcs. Most of the villains in ''Stardust Crusaders'' go entirely unnamed in the original publications, only to be given names later on in the volumized editions and art books. This was particularly egregious when Viz translated it into English the first time around and gave the name "Rubber Soul" to the character Steely Dan, when Rubber Soul is the name of a character that appears earlier but goes unnamed. The anime series fixes this by at least giving characters' names in eyecatches. Later parts of the manga also give character names and Stand names either explicitly in the text, as part of a cover page, or again later in the volume versions.

** [[CrackIsCheaper .Hack//Your Money is Ours]] ......

* Want to know the {{backstory}} for ''Anime/OnePieceStrongWorld'''s villain, Gold Lion Shiki? You have to either go read the supplemental "Chapter 0" or watch the OVA based on said chapter.

* ''Manga/XxxHoLic'' and ''Manga/TsubasaReservoirChronicle'' have ended up so interconnected that it is nigh impossible to understand one without reading the other. And even then you wish you had the option to phone Ohkawa and demand an explanation.

* In ''Manga/DeathNote'', you never do find out L's real name. Unless, of course, you get the book with all the supplemental information in it or watch the [[Film/LChangeTheWorld last live action film]]. It's [[spoiler:L Lawliet]].

** 'Anime/PokemonTheFirstMovie'' could not be fully understood without ''[[Radio/PokemonTheBirthOfMewtwo The Birth of Mewtwo]]'' CD drama to accompany it. It doesn't help that the partial animated adaptation of that CD Drama, which was basically new scenes added to the beginning of later Japanese releases of the first movie and treated as additional parts of the film, was cut out from the dub (an English adaptation was available, but only on the bilingual Japanese DVD releases). Fortunately, 4Kids later included this for American fans in the ''Anime/PokemonMewtwoReturns'' DVD.

** 'Anime/PokemonTheFirstMovie'' could not be fully understood without the CD drama ''Birth of Mewtwo'' to accompany it. It doesn't help that the partial animated adaptation of that CD Drama, which was basically new scenes added to the beginning of later Japanese releases of the first movie and treated as additional parts of the film, was cut out from the dub (an English adaptation was available, but only on the bilingual Japanese DVD releases). Fortunately, 4Kids later included this for American fans in the ''Anime/PokemonMewtwoReturns'' DVD.

* A large amount of key information useful in understanding the story can only be found in the supplemental materials for ''Anime/NeonGenesisEvangelion''.

* The ''Manga/KokoWaGreenwood'' OVA literally directs the viewer to a specific chapter of the manga to explain a reference.
** This is because the second OVA happens after the next 4 (it even refers obliquely to the plot of 5 and 6). AND it's a sequel to a story they didn't animate.

* ''Anime/PokemonTheFirstMovie'' could not be fully understood without the CD drama ''Birth of Mewtwo'' to accompany it. It doesn't help that the partial animated adaptation of that CD Drama, which was basically new scenes added to the beginning of later Japanese releases of the first movie and treated as additional parts of the film, was cut out from the dub (an English adaptation was available, but only on the bilingual Japanese DVD releases). Fortunately, 4Kids later included this for American fans in the ''Anime/PokemonMewtwoReturns'' DVD.

* The canon of ''Anime/WeissKreuz'' is distributed across two anime series and an OAV, a good many drama [=CDs=], and several manga and short stories. Fortunately the first anime series is pretty well self-contained, but in the absence of the material from the drama [=CDs=] the drastic changes between it and sequel series ''Weiss Kreuz Gluhen'' make no sense at all. Naturally, [[NoExportForYou only the two anime series have been officially released to western audiences]].

* The ''[[Anime/SuperDimensionFortressMacross Macross]]'' [[TheVerse universe]] includes significant amounts of supplementary canon from books, comics, and video games in addition to the series and [=OVA=]s that were actually filmed.

* At the end of every ''Manga/MiraiNikki'' volume, there is an {{Omake}} that may explain certain things that were not very obvious, such as how and why the 3rd, 4th and 9th were targeting each other, and how they began to focus on Yukki. It also gives a little background info on some of the other future diary holders.