[[folder: ''Webcomic/Axis Powers Hetalia'' ]]
* [[spoiler: Italy]], of all people, in ''HetaOni''.
* In ''Fanfic/HumanCuriosity'', America pretends to be tactless and unaware that he's pissing off Arthur Kirkland, in order to pull off Arthur's sunglasses and [[ItMakesSenseInContext see if he really is England]]. It's noted that one of the good things about America tending to be TheDitz is that no one notices the rare instances when he's only ''pretending'' to be stupid for his advantage.
[[folder: Cross Over ]]
* Kyon, in ''Fanfic/KyonBigDamnHero''. He is shown to be highly fluent in English, easily beating the brigade in Scrabble, very skilled in chess[[note]]Asakura's best against him was a single stalemate[[/note]], and invokes GratuitousEnglish. He also learns German from Tsuruya extremely quickly. Aside from language skills, Kyon also managed to convince a renegade time traveler to pull off a StableTimeLoop for him, or risk being killed, because Kyon can go back in time to take his place, thus rendering his ContractualImmortality moot.
* [[spoiler:Cruise Control]] in ''WebAnimation/TurnaboutStorm''. This particular case is more PlayedForDrama than usual, as they had seen themself more or less forced into it [[spoiler:thanks in part to Ace Swift blackmailing Cruise into losing to him. Cruise thought the whole act would be more believable if he thought and acted like a general loser as well]].
* [[spoiler: Princess Peach]] of all people in ''[[FanFic/NewLookSeries Link's New Look]]''
* Darcy Lewis in ''Fanfic/ChildOfTheStorm''. No one expects someone that looks like her and talks like her to be smart, perceptive and armed with a taser, and there is a good deal of evidence that she uses it to her advantage.
[[folder: ''Manga/Death Note'' ]]
* [[Manga/DeathNote Light]] in ''FanFic/MyStupidReality'' has faked being BookDumb all his life in order to protect himself from L. He has it down to an art:
-->'''Light:''' One does not just randomly select a question or 2 and try to get them wrong. No. Nor do you do it to every 4th question or some other such ridiculous, predictable pattern like that. [[TheChessMaster The key lies in, like all things, strategy]]. You need to choose ahead of time a subject or 2 you're awful at, a few you're neutral, and 1 you're good at. Then whenever you get homework, consistently get the same basic principals wrong, and get it wrong on the test as well. Also, you have to make a show of not paying attention in class, or else suspicions will be raised, and you'll be given a special "learning disability," and assigned a tutor pronto.
[[folder: ''Detective Conan'' ]]
* A few fanfic authors like to play with the idea that Richard Moore is aware of what Conan is doing, or faking being asleep. Has a basis in the simple fact that being injected countless times with the same sleeping drug will eventually result in the body resisting it.
[[folder: ''Franchise/Harry Potter'' ]]
* Crabbe and Goyle are quite commonly described as doing this. Sometimes they are just shy or quiet, and that combined with their appearance, their love for food and their status as Draco Malfoy's cronies make people think they are stupid. Other times they are actively pretending to be stupid so that people won't expect anything of them. In both cases they either actually like Draco and he likes them, or they protect Draco physically (as is implied in canon) and he protects them socially. In one particular fic, they weren't stupid, but since they suffered from undiagnosed dyslexia, everyone thought they were.
* In ''[[http://www.fanfiction.net/s/8499891/1/Whispered-Words Whispered Words]]'' Harry fakes a head injury in an attempt [[RefusalOfTheCall to make Dumbledore and the rest of the Wizarding World leave him alone and not drag him into]] ''[[RefusalOfTheCall their]]'' [[RefusalOfTheCall war.]]
[[folder: ''Anime/Girls Und Panzer'' ]]
* In ''Fanfic/BoysDoTankary'', [[OriginalCharacter Gage]] pretends to be drunk (although he ''genuinely is'' TheAlcoholic) when Vincent comes into the bar to recruit him as the parts coordinator, so that Gage can confirm that Vincent was the one who killed Nyra.
[[folder: ''Western Animation/My Little Pony Friendship Is Magic'' ]]
* ''FanFic/WereGonnaGetThereSoon'': [[WesternAnimation/MyLittlePonyFriendshipIsMagic Der]][[TheKlutz py]] isn't a genius, but she's more aware of what [[AllOfTheOtherReindeer other]] [[WellDoneSonGuy ponies]] say and think of her than they give her credit for.
[[folder: ''Manga/Naruto'' ]]
* Naruto status as dead last in the academy and IdiotHero everywhere is at times depicted as this in most fics. However, the reasons as to why are what really make it enjoyable to read. For example:
* In ''Blind'' the Hyuuga train their kids at the age of 3 (according to this fic that's the youngest you can mold charka). Naruto just so happens to be Hyuuga Hiashi's adopted guest/son and he and Hinata can pass the Genin Exam with flying colours. The problem however is that Hinata is [[CaptainObvious blind]] so her clones and henges come out black and white so she can't pass thusly her class and villagers (except Hiashi. He's is a [[GoodParents good father here]]) brand her a dope. Naruto [[CrowningMomentOfHeartwarming keeps failing (Hiashi himself has been teaching Naruto to be a hyper-competent ninja) to stay with her while developing a jutsu to help her see.]] It should be noted that Hinata knows one of the Second Hokages jutsus and Naruto knows Kage Bushin and the Hiraishin.
* Kakashi in ''FanFic/FromHisExcerpts'' by Phoenyxx. Kakashi speaks fluent English, but hides it from the professors, resulting in little gems like these:
-> "Squid…Like…No magic."
-> Oh. Professor Flitwick chuckled lightly, "I believe the correct term is squib."
->"Yes, squid. It is what I say."
* In ''Legacy of the Rasengan'' Naruto is a creator of simple-to-use yet effective jutsus (simple as in easy to activate and tweak), thinks before he acts, is very observant but acts like his canon self to hide it. The only ones who know (at first) he is playing dumb are Kakashi (due to Naruto outwitting him during the bell test and carefully observing Naruto "Take in information, process it instantly, then act in a manner expected of his buffoon self." ), Hinata ([[ShipTease he doesn't put up the charade when they're alone together]]) and Shikamaru (connected the dots like Kakashi). As is common with the trope they call it dumb luck if he pwns with wits/acts unusually perceptive and jaw-drop when he shows jutsu. Everyone eventually figures it out during the Chunnin Exams after he [[CrowningMomentOfAwesome displays a jutsu that works like Jyuuken and]] '''[[CrowningMomentOfAwesome CLEAVES THROUGH NEJI'S ROTATION]]'''!
* Kaede Mizuno in ''FanFic/AGrowingAffection'' operates using this trope, she wants her enemies to think she is just a pretty face who was promoted due to her family connections. She is in fact quite intelligent, and goes toe-to-toe with some of the strongest characters in the story.
[[folder: ''Anime/Neon Genesis Evangelion'' ]]
* ''Matters of Faith'' has [[EmotionlessGirl Rei]] [[TeenGenius doing]] '''[[ReluctantMadScientist SCIENCE]]''' [[AlternateCharacterInterpretation without anyone knowing]]. When one of Shinji's innocent comments back her against a wall in a conversation, [[WrongGenreSavvy she suspects him of doing this]] (with the justification that it's probably [[InTheBlood Gendo's genes]] in play).
[[folder: Real Person Fic ]]
* In ''Fanfic/WithStringsAttached'', the four all pretend to be naïve, useless fools when they first start journeying with the Hunter, because they take a massive dislike to him the moment he enters the scene. Their intent is to gradually reveal their power as they travel so they can humiliate him. This turns out not to be the best idea they ever had.
[[folder: ''Sailor Moon'' ]]
* During the late '90s, Usagi of ''SailorMoon'' practically ruled this trope. It was all the rage for fanfic writers to make Usagi into a GodModeSue who was only pretending to be an idiot, often by leaving the Inners and dropping the act. That she still can't write proper hiragana as queen and routinely swipes her kid's candy in the canon is conveniently ignored.
** She is TheDitz in the anime, but shows that she is actually pretty smart in the manga, especially as it goes on and the burdens of leadership take their toll. Venus can be considered another case as well, since it is hinted that she speaks fluent English, a language that is just as hard for the Japanese to learn as their own language is for native English speakers. (They're in completely different language families, so have no common baselines).