History SleeperHit / AnimeAndManga

* The ''Gridman Universe'' franchise has practically become famous for this, with both the ''Anime/SSSSGRIDMAN'' and ''Anime/SSSSDYNAZENON'' animes alongside the [[Anime/GridmanUniverse self-titled film]] ''well'' exceeding expectations from the series. While all three featured low-key promotional stints prior to their debuts, they drew in ''far'' more viewers once they hit the screens, winning them over due to high production values, well-rounded characters, and introspective Aesops that don't intrude rudely on the main story.

* ''Anime/YuriOnIce'' was this for the fall 2016 season, both in Japan and abroad. Many assumed it would only be a modest success, since it was an [[AnimeFirst original anime]] that focused on the not-very-mainstream sport of figure skating. However, it steadily grew in popularity, which exploded when the seventh episode aired and [[spoiler:both the YaoiFangirl crowd and the LGBTFanbase caught wind that the main character really ''did'' end up with his coach rather than it just being ShipTease with [[BaitAndSwitchLesbians the rug pulled out from under the shippers later]]]]. In the West, all you have to do is look at Website/{{Crunchyroll}} at the beginning and end of the season; at the start, the only thing they were promoting besides ''Naruto'' was the {{fanservice}} romp ''Manga/{{Keijo}}''. By the time the last episode of ''Yuri!!!! on Ice'' aired, it had supplanted ''Keijo!!!!!!!!'' and every other show on the site as the most popular and most advertised series of Fall 2016. It was also hugely successful in Japanese Blu-ray and DVD sales, surpassing fifty thousand copies in the first week and becoming the fourth best-selling anime of all time less than a year after its release.

* ''Anime/KemonoFriends'' is an ''incredible'' example. As a [[NoBudget conspicuously low-budget]] CG anime based on a failing franchise, it wasn't on anyone's radar. Even the creators expected it to flop -- the mobile game it was meant to promote was cancelled before the anime aired, its manga wasn't talked about at all when it premiered, and they hadn't planned to sell any merchandise. As it turned out, the generally decent writing, solid character designs and surprisingly compelling OntologicalMystery made for a solid watch, and it ultimately became ''extremely'' popular through [[MemeticMutation internet word-of-mouth]]. Its first episode became the most-watched anime episode on Website/NicoNicoDouga; disc sets and merch quickly sold out, and the DoItYourselfThemeTune reached #3 on Japan's iTunes rankings. People began reading the manga in earnest to see the connections between it and the show, and eventually the clamor to bring back the mobile game became so great that Nexon backtracked and said they were considering reviving it while another company created ''two'' of them in its place.

* ''Manga/RankingOfKings'', the series is authored by Sousuke Tooka, a man who decided that at 41 years old in 2017 he should quit his office job and draw manga because he wanted a little more excitement in his life by fulfilling a dream; the guy's art had the clear beginner's crude look but he pushed forward in a relatively small underground anthology called Manga Hack, ''Ranking of Kings'' became a dark horse in the online anthology, scoring dozens of thousands hits per chapter as the years went by which prompted the publisher Creative Entertainment to partner with fellow publisher Enterbrain to produce physical manga volumes in 2019. In 2021 the series received an anime adaptation by WIT Studio, the anime opened the gates for a worldwide audience that embraced the fantasy tale quite easily, more than the manga ever reached at first; that all became quite the unexpected tale of success of a salaryman becoming a mangaka at such a late time, for this is a profession where people are expected to start in their younger years.

* This happened when Kyoto Animation adapted the ''Literature/HaruhiSuzumiya'' LightNovels, which had limited underground success up to that point. Thanks to the anime adaptation, it became one of the most popular anime franchises of the 2000s and a huge CashCowFranchise. Unfortunately, the demotion of Atsushi Ito, the Kadokawa executive who had pushed for ''Haruhi'' to be animated, was one of the factors that led to [[FranchiseKiller the death of the franchise]] by the beginning of TheNewTens.

* In spite of a very quiet release on Jump's digital service and being from an almost completely unknown author, ''Manga/SpyXFamily'' absolutely ''shattered'' expectations by quickly becoming one of the most popular series on Manga Plus, and ''the'' most popular series on Jump+ in the span of just four months, before then becoming not just the best selling new series of the year, but also one of the best selling debuts for a Shueisha manga for that entire decade − volume 2 sold over 100,000 copies in its first week alone, something not even modern Jump hits like ''Manga/MyHeroAcademia'' or ''Manga/ThePromisedNeverland'' managed in their early days. This quickly led to the series getting licensed by Viz for a physical release despite not even being a year old.

* ''Manga/BocchiTheRock'' is a comedic slice-of-life {{Yonkoma}} series whose animated adaptation people weren't expecting much from (especially with its [[{{Creator/Cloverworks}} studio's]] mixed reception in past years and a season packed with awaited adaptations of heavy hitters such as ''Manga/SpyXFamily'', ''Manga/{{Bleach}}'', ''Manga/ChainsawMan'' and ''Webcomic/MobPsycho100''). However, against all odds, the anime quickly became one of the breakout hits of the season thanks to its relatable protagonists, creative animation direction, and frequent use of [[ArtShift different art and animation mediums]] for comedy. It was even announced that pre-orders of the first Blu-Ray sold out on Amazon.

* Believe it or not, one of the series which drawed most attention from anime viewers, at least in Asia, during the heated-up Winter 2021 season is ''Anime/PuiPuiMolcar''. The series [[WidgetSeries remains largely unknown in the West]], but watching a bunch of [[RidiculouslyCuteCritter unbelievably cute]] [[AnimalVehicleHybrid vehicles that look and act like giant guinea pigs]] doing things for 3 minutes surely doesn't hurt much. In fact, [[https://twitter.com/molcar_anime its official Twitter account]] has the highest numbers of followers among all the new titles aired that season (sitting over 300k which is ''at least three times'' that of the next contender ''Idoly Pride'') and ranked ''5th overall'' (as of [[https://twitter.com/anime_follower/status/1359188215899426819 early February]] it's just behind four sequel titles aired), with numerous fan art with different Molcars spread around the Internet. Even the producers are surprised about its popularity.

* ''LightNovel/DemonKingDaimao'' had a very average reception in Japan, where it was written off as an action and fanservice show. In the U.S., however, it got good ratings on the Creator/AnimeNetwork, only rivaling ''Manga/HighschoolOfTheDead''. As a result, it was able to get an English dub, and its [=DVDs=] were able to sell just as well as ''HOTD'', ''VisualNovel/{{Clannad}}'' ''and'' ''Anime/AngelBeats''. Was it the fanservice or the action that got its attention? Regardless, it's a rather odd example of this, seeing as there doesn't seem to be much of a fanbase compared with the other series.

* ''LightNovel/MyNextLifeAsAVillainessAllRoutesLeadToDoom'' came out of nowhere to become ''the'' smash hit of the Spring 2020 season. At first, many people who read the synopsis before release dismissed it as just another Isekai with a really silly premise. However, after the show was released, fans began to fall in love with the wholesomeness and cuteness of Catarina's character, and word-of-mouth quickly spread about its rare mixed-gender harem premise. It became ''so popular'' that her ships won [[https://twitter.com/AniTrendz/status/1282055979274657792 5 of the 10 'best couples' of Spring 2020]] in survey by Anime Trending. A second season was thus announced before the first had even finished airing.

* ''LightNovel/BofuriIDontWantToGetHurtSoIllMaxOutMyDefense'' was a relatively unknown light novel prior to it receiving an anime adaptation, and even once it did, it didn't garner much attention due to its premise as a VRMMO-centered series, which there were plenty of. Once it did start airing, the series quickly gained a strong community following for its light-hearted take on the VRMMO genre, consistently clean animation, and many entertaining scenarios courtesy of its protagonist, to the point where a second season was immediately announced at the end of Season 1.

* Initially, many wrote the anime adaptation for ''Literature/KonoSuba'' off as yet another generic harem series and the fact that Creator/StudioDEEN was working on it didn't help matters either, not to mention that it was only scheduled to have 10 episodes rather than the usual 12. However, after the first episode aired, people were surprised at how funny the show actually ended up being and loved its charming brand of self-aware parody humor especially when many "trapped in a video game" anime usually take themselves [[SeriousBusiness far more seriously.]] It was one of the most well-received anime in the [[Winter2016Anime Winter 2016 season]] and it absolutely dominated the sales charts in Japan, and a second season was announced at the end of the final episode.

* ''[[Manga/ArpeggioOfBlueSteel Arpeggio of Blue Steel: Ars Nova]]'' was not expected to become one of the more acclaimed manga adaptations during the Fall2013Anime season, as its source manga filled a rather niche readership. However, it gathered so much critical acclaim that, in the following year, famed magazine ''Newtype'' handed out fan-selected prizes to various shows, and among them ''Ars Nova'' won several top prizes (as well as many runner ups), lining it up along hit shows like ''Anime/KillLaKill''.[[note]]For reference, here's [[http://www.crunchyroll.com/anime-news/2014/10/11/kill-la-kill-and-the-idolmster-movie-and-win-big-at-newtype-awards a list of awards]] handed out after ''Newtype''[='=]s web voting.[[/note]]

* ''Anime/OsomatsuSan'' is a sequel to and was based on the older Fujio Akatsuka work ''Manga/OsomatsuKun'', but it was only expected to have moderate success thanks to nostalgia. However, the series was one of the breakout hits of the Fall2015Anime season. Even the staff has no idea how it became so radically successful.

* ''Anime/YuriOnIce'' was this for the Fall2016Anime season, both in Japan and abroad. Many assumed it would only be a modest success, since it was an [[AnimeFirst original anime]] that focused on the not-very-mainstream sport of figure skating. However, it steadily grew in popularity, which exploded when the seventh episode aired and [[spoiler:both the YaoiFangirl crowd and the LGBTFanbase caught wind that the main character really ''did'' end up with his coach rather than it just being ShipTease with [[BaitAndSwitchLesbians the rug pulled out from under the shippers later]]]]. In the West, all you have to do is look at Website/{{Crunchyroll}} at the beginning and end of the season; at the start, the only thing they were promoting besides ''Naruto'' was the {{fanservice}} romp ''Manga/{{Keijo}}''. By the time the last episode of ''Yuri!!!! on Ice'' aired, it had supplanted ''Keijo!!!!!!!!'' and every other show on the site as the most popular and most advertised series of Fall 2016. It was also hugely successful in Japanese Blu-ray and DVD sales, surpassing fifty thousand copies in the first week and becoming the fourth best-selling anime of all time less than a year after its release.

* ''Manga/BocchiTheRock'' is a comedic slice-of-life {{Yonkoma}} series whose animated adaptation people weren't expecting much from (especially with its [[Creator/Cloverworks studio's]] mixed reception in past years and a season packed with awaited adaptations of heavy hitters such as ''Manga/SpyXFamily'', ''Manga/{{Bleach}}'', ''Manga/ChainsawMan'' and ''Webcomic/MobPsycho100''). However, against all odds, the anime quickly became one of the breakout hits of the season thanks to its relatable protagonists, creative animation direction, and frequent use of [[ArtShift different art and animation mediums]] for comedy. It was even announced that pre-orders of the first Blu-Ray sold out on Amazon.

* ''Manga/BocchiTheRock'' is a comedic slice-of-life {{Yonkoma}} series whose animated adaptation people weren't expecting much from (especially with its studio's mixed reception in the past year and a season packed with hyped adaptations of heavy hitters such as ''Manga/SpyXFamily'', ''Manga/{{Bleach}}'', ''Manga/ChainsawMan'' and ''Webcomic/MobPsycho100''). However, against all odds, the anime quickly became one of the break-out hits of the season due to its relatability, expert comedy, creative directing, and its willingness to [[ArtShift mix and match different styles and looks of animation]] in order to better deliver its gags. It was even announced that pre-orders of the first Blu Ray sold out on Amazon.