Something Only They Would Say / Anime & Manga

• Afro Samurai: Possible Played for Laughs example. At one point during Afro’s fight with the Afro Droid, Ninja Ninja gets temporarily confused as to which is the real Afro.
  Ninja Ninja: You’re bleedin’, bruh. W-wait a minute, prove to me that you’re you. Say somethin’ to let me know it’s you.
  Afro: (has said this to Ninja Ninja on more than one occasion) Shut. Up.
  Ninja Ninja: Oh, it is you!
• Ah! My Goddess: When Urd splits into good and evil parts, she actually does this to herself, saying "if you're the real Urd, you should know where Keiichi has his dirty magazines, etc." Followed by answering those questions.
• Cool Old Guy Joseph Joestar is forced to rely on this in JoJo's Bizarre Adventure: Stardust Crusaders. After being killed by Dio Brando and having his blood drained by the vampire, he undergoes an emergency blood transfusion to try to bring him back to life. Upon awakening and seeing Dio's corpse, his first thought is to play a joke on his grandson, Jotaro, and pretend to be possessed by the vengeful spirit of Dio. Jotaro is ready to punch his face in, but Joseph narrowly avoids being killed a second time by answering questions from Jotaro, such as "Who starred in the 1981 remake of Tarzan?" (Bo Derek) and "Who sang 'Eat It?'" ("Weird Al" Yankovic). As Jotaro puts it, "Only you would know such stupid things."
  • Earlier in the same arc, Polnareff knows a version of his Back from the Dead sister Sherry is the real deal when she admits she still feels guilty about an incident from when they were younger (she fed his favorite exotic fish to the cat). Doesn't mean she didn't come back wrong, though.
• Used as a red herring in Case Closed, where Jodie is routinely seen using a catch phrase ("A secret makes a woman a woman") belonging to Vermouth, the Black Organization's master of disguise, who bears some resemblance to Jodie. Turns out that Vermouth said the same phrase to Jodie after killing Jodie's parents.
  • Played with much earlier in the series, in episode 2: Conan reveals he knows about the mole on Agasa's butt to try to convince Agasa he's really Shinichi in a kid's body - but Agasa just assumes Shinichi's been blabbing. Instead, Conan convinces Agasa by doing a Sherlock Scan to figure out where he's been, proving he's really Shinichi via ability instead of knowledge.
  • Also when Akai Shuuichi is disguised as Okiya Subaru, he says "the blame is fifty-fifty", a common phrase he used, which provides the clue of who Akai was hiding as to Jodie after she realized his death was faked.
• In the end of the first season of K, the Silver King shows up in the body of a high school boy, and before he can worry about how to convince the others in the room that it's really him, the Gold King calls the phones in the room. When Kusanagi answers, the Gold King tells him, "There should be a man standing somewhere near you with a silly look on his face. Put him on the line, will you?" Sure enough, Kusanagi looks up and the Silver King is wearing that exact expression - after not having seen the Gold King for about seventy years, it still holds true.
• In the second episode of Valvrave the Liberator, Haruto has somehow found himself in the body of a Dorssian spy (who we will later come to know as L-elf). After rescuing his friends, Haruto tells them it's really him. How does Kyuma decide to test this? Several rounds of rock-paper-scissors. Haruto loses all of them. "Alright, it's you."
• In an early episode of YuYu Hakusho, Yusuke's deceased spirit possesses Kuwabara's body to tell Keiko that he's coming back to life soon, so he needs her to take care of his body. However, Yusuke's been unable to convince anyone else that he's been telling the truth, so instead, he approaches her from behind, suggestively compliments her "Nice skirt!" (a callback to a scene in the first episode where he flipped her skirt) and grabs her breasts. This causes her to slap him across the face while shouting "Yusuke, you jerk!" out of habit, after which she's much more receptive of his claim to be Yusuke in Kuwabara's body. Since that wouldn't fly outside of Adult Swim, the Bowdlerised Toonami version cuts out the boob-grabbing.
• In Baccano!, Rachel and her associates at the Daily Days figure out that the Rail Tracer was actually the train conductor, because the Rail Tracer knew Rachel was a stowaway and asked for her ticket.
  • Later, Claire Stanfield reveals himself to Rachel as the aforementioned rail tracer by making a comment about her ticket purchases.
  • You know how that demon that started the whole thing is always saying "maa, ii"/"well, no matter"? You know how that guy Ronnie who works for the Martillos is always saying the same thing?
• In Sailor Moon, Chibi-Usa knows that a monster disguised as her mother is a fake, because her mother calls her "Small Lady," not "Rabbit," which is the Black Moon clan's name for her. A similar situation occurs in the Sailor Moon: Another Story game, where Nergal disguised as Sailor Pluto is given away because she calls Chibi-Usa "Princess," while Sailor Pluto would normally use the same "Small Lady" nickname.
  • Also in one of the final episodes of Sailor Moon S, Mistress Nine reverts to using Hotaru's regular body to get Moon to give her the Holy Grail (the "Purity Chalice" in the U.S. TV broadcast version). When Moon finds her among the ruins of the Mugen Academy, she realises the person she is talking to is not Hotaru when the latter calls her by her civilian name, Usagi: the real Hotaru met Moon before but only as Usagi, so Hotaru would never know that Usagi was Sailor Moon.
  • In an earlier episode, as Usagi is being given a ride by Haruka, she recognizes the latter's speech about "people only surviving by trampling on others" as the same words Sailor Uranus spoke.
  • Pretty Guardian Sailor Moon has a great, if narmy, scene, where Sailor Moon exhausts herself trying to protect Tuxedo Kamen and nearly falls down the stairs. Tuxedo Kamen catches her and asks if she's an idiot. SM automatically retorts with "who are you calling an idiot" before realizing their dialogue mirrors the one between her and Mamoru after the latter saved her from being run over by a car. Cue dramatic unmasking.^note One-sided, as Mamoru already knew her identity by that point.
• In both the Visual Novel and anime of Fate/stay night, Archer says and does things occasionally that hint at his true identity as a future Shirou Emiya, most damning of which is "Trace on", the same thing that Shirou always says when he activates his magic.
• In Fullmetal Alchemist, Edward and Ling are wary of one another since either one could be the impostor Envy, while trapped in Gluttony's stomach. Ling proves himself to Edward by offering to recite, in perfect order, all of the items on the room service menu from the hotel where they were staying. He then starts to press Ed's Berserk Button by making a reference to his shortness; when Ed pitches his characteristic tantrum, Ling knows he's the real thing. Ironically, when Envy does show up, they aren't even bothering with a disguise.
  • Zigzagged when Bido recognizes the second Greed due to his signature speech. While he correctly identifies Greed as a result, Greed himself doesn't recognize Bido until after killing him and suffering when his lost memories come back.
  • Later, after Greed's Anti-Heroic BSoD, Ed discovers Ling in the hut they used as a fallback after Mustang's guys, the Elrics, and Ling's party worked together to capture Gluttony (interestingly the last place in the normal world Ling was seen alive, really, since the two of them got to Father's base by way of Gluttony's stomach) and Ling's falling over and asking for food is taken by Ed as a sign that it's really him.
  • Parodied in episode 14 of 4koma Theater:
    Roy Mustang: "When we're alone, the Lieutenant calls me cutie pretty lovely lighter!" (gets shot twice)
  • The above is a parody of an actual line used between Riza and Envy when they corner him. Roy has gone on the warpath against Envy when Envy revealed he killed Hughes. Riza inverts the trope by putting a gun on Roy and seemingly invoking this by saying that when alone, Roy always called her Riza. The Roy turns out to be Envy in disguise who ends up just confirming it is him due to Riza's trickery.
  • A variant from when Ed asks both Alphonse and Winry what the latter told Al when they were kids for why she wouldn't date either of the brothers. Both of them answer that Winry told him she doesn't date guys shorter than her. Because this a memory of Al that Ed had no idea before he asked, it confirms that Al's soul really is bound to the armor.
  • Riza comes across a suit of Animated Armor claiming to be the executed Serial Killer "Barry the Butcher". Officer Falman is able to confirm it's really Barry's soul bound to the suit by asking him for information about his murders, which he answers in such detail and fondness that it leaves no doubt it really is him. Barry even corrects Falman when he intentionally gives the wrong date for one of his killings to see if Barry would slip up.
• Akumetsu's mask in the eponymous series really isn't that good for concealing his identity, what with leaving much of his face including his distinctive hair and eyebrows and most of his grin visible, but it's by his 'ya know' that our initial viewpoint character recognizes him in the first arc. When he comes in and coincidentally kicks off his terrorist career by chopping up the Dirty Old Man who'd just hired her in her new career as a teen prostitute with an axe. They're both normal high school students again the next day. (Her for real, him only apparently.)
  • He doesn't care all that much if he's recognized, since Akumetsu has a policy of dying on the job and any one of him probably has an alibi, and if he doesn't who's going to believe that the terrorists are a clone army, even after dissecting dozens of identical bodies? Also, the one who saved her wasn't the one she actually knew, even though they're all bizarrely similar for several dozen identical twins brought up separately, right up to the 'ya know.'
  • The scene gets a callback later, though, with one of the not-important-enough-to-be-targetted minion with the underwear on his head tracking the girl down because she said 'Shou!' when Akumetsu came in and said his Catchphrase.
• In the final episode of Durarara!!, Mikado guesses that someone in a chatroom is Kida. The response? Grading Izaya on a scale of 1-10 with the square root of three, a callback to an earlier scene with the pair.
• Happens with Tetsuya in Metal Fight Beyblade. He wears a (actually very convincing) disguise to try and steal all of Gingka's beypoints, but is recognized at the last minute because of his alias 'Nigel Crabbypants'. Being openly obsessed with crabs does have a downside! Who knew?
• In Soul Eater, when Maka first shows up in the black room, Soul wonders if she's just an image created by the Little Demon. Her response is to hit him over the head with a book, something only she would do. After that, he admits that "Yeah, it's Maka."
• Naruto:
  • During the Chunin Exams arc, Sasuke gives Naruto and Sakura a lengthy passphrase to identify them with, since there are enemies about who might impersonate them, despite Naruto's complaints. Naruto goes off to relieve himself, and upon return identifies himself with the correct phrase. Sasuke promptly beats up the imposter, as the real Naruto wouldn't be able to remember it and complained about it beforehand. Predictably, when the real Naruto shows up to help out, he admits that he forgot the passphrase completely.
  • Defied during the fourth Ninja World War arc. Chouji proposes something to this effect to make sure that they aren't being impersonated by white Zetsus, but Shikamaru says that the clones have been able to fool the ninjas with this method, as "Sometimes a lucky guess ends up being right". Only Naruto has a foolproof way of telling the real ones from the fakes and this is due to his recent powerup allowing him to sense different chakras.
• In Zone of the Enders: Dolores, i, James realizes that the Orbital Frame Dolores is connected with his supposedly-dead wife when he hears her singing a lullaby she used to sing to their children.
• This is how Leafa finds out Kirito is really Kazuto in Sword Art Online when he blurts out of his plan to save Asuna from Sugou's clutches as this reminds Leafa that he has feelings for Asuna.
• In Gintama:
  • This is how the Yorozuya gang ends up identifying all of the players they run into while playing Monkey Hunter as people they know outside of the game. Some examples include Katsura using his Catchphrase, and Hasegawa lamenting the fact that he's unemployed.
  • Katsura is especially prone to this in general, as referring to him by anything other than his name frequently prompts him to use his Mad Libs Catchphrase in the format of "It's not *noun*, it's Katsura!". He's managed to blow his cover on multiple occasions because of this.
• This trope plays quite a role in Honoo no Alpen Rose: One of the final proofs that Alicia/Jeudi's blind mother Helene needed to deduce that the one calling herself "Alicia" was not her daughter but a Body Double was whether she knew or not the "Alpen Rose" song, composed by Alicia/Jeudi's Disappeared Dad Friederich. The false Alicia, Mathilda, had claimed not to remember the song due to Trauma-Induced Amnesia. The real one, Jeudi, recalled the song enough to either write down the lyrics (manga) or sing it in public (anime).
• Aquarion Evol has a variant. When "transfer student" Jin can identify an attacking Abductor by name, Yunoha is able to make the obvious connection.
• A variation occurs in an episode of Pokémon the Series: XY — Serena meets a girl who introduces herself as Ariana (actually Kalos Queen Aria in disguise) and challenges her to a double battle, during which she makes a particular pose while giving orders. Later on, Serena watches one of Aria's performances and sees her make the same pose, at which point she puts two and two together.
• In Pokémon Adventures, X realizes that Y is actually Essentia in disguise when she 1) doesn't immediately apologize for separating from him and 2) calls him 'anata', which roughly translates to 'dear'.
• A non-verbal variant occurs in the opening battle of Mobile Suit Gundam Wing: Endless Waltz, when Duo is attacked by a unique enemy mobile suit, and after noticing that its method of fighting is to simply empty as many bullets in his general direction as possible, he recognizes that Trowa is the one piloting it.
• One of the hints before The Reveal that Largo was a resurrected Brian J. Mason in Bubblegum Crisis was boasting to Priss "This is the look of the true winner!", which were the words he said to Sylia at the start of the battle that originally killed him. The English dub added to this by having Largo call Leon "little puppy", which he also called Leon as Mason.
• Used in Overlord (2012) when the leader of a group of adventurers hastily claims they came to the Tomb of Nazerick on behest of an old friend of its ruler. Ainz has been looking for such old friends and holds his assault, asking who the message is for. The adventurer says it's for Ainz Ooul Gown...and promptly outs himself as a liar. The correct answer was either Momonga, Ainz's gamertag from when YGGDRASIL was an MMO, or Satoru Suzuki, his real human name.
• The Promised Neverland: Isabella is seen humming to an unspecified melody a few times. Near the end of the first arc, we learn that this was a song written by her Lost Lenore Leslie. When she discovers Ray humming it, she realizes that he's her son — he remembers her singing it to him while she was pregnant with him. Because he noticed her singing it too, he found out sometime before that that she was his mother.
• SoltyRei:
  • Solty is taught a song, "Return to Love", by Rose. When she sings it around Roy, he realizes that Rose is his missing daughter Rita, because that song only exists on a rare record that he used to play for his family to listen to.
  • At the end of the anime, Roy and Yuto are able to find Solty in the debris of space when they hear her humming the song.
• A Certain Magical Index: Spoofed late in New Testament, when Shiage Hamazura is trapped inside a full-body suit he cannot remove, he tries this method to convince his girlfriend Takitsubo that's it's really him inside the suit. Unfortunately, the things he tries saying to convince her are not only embarrassing to her, but they are things he'd noticed since they started living together that she didn't know he'd noticed (mostly revolving around her morning and bedroom routines and hygiene). She and the rest of ITEM start attacking him thinking he's a pervert who'd put hidden cameras in her bedroom.
• Inverted in The Quintessential Quintuplets when Ichika tries to confess to Fuutarou by posing as Miku because she didn't have the courage to do it as herself (and also to sabotage Miku's own confession). Fuutarou quickly calls her bluff because, at this point, he knew the real Miku was in love with him and she would never say that.
• My Hero Academia: At the end of the first round of the Joint Training Arc, Jurota has Shinso on the ropes when he hears Hiryu's voice telling him to look behind him. At first, Jurota thinks it's just Shinso using his support item, right up until the voice refers to him as "Apocabeast", a nickname Hiryu came up with when they were alone. Sure enough, it's the actual Hiryu trying to warn Jurota before Tsuyu tongue-whips them into each other.
• In That Time I Got Reincarnated as a Slime, Rimuru and Benimaru come up with a pass phrase for Rimuru to check if he lost his rationality after becoming a true Demon Lord, with the test consisting of Benimaru asking about Shion's cooking and Rimuru answering that it stinks. Following his ascension to a Demon Lord, Benimaru asks him for the pass phrase... while Shion is holding onto Rimuru. Rimuru is able to Take a Third Option from his Ultimate Skill Raphael by saying that he is supposed to say Shion's cooking stinks and that it was Benimaru's idea, thus diverting Shion's wrath (and cooking) for the time being.
• Played for Laughs at the end of Dragon Ball Z: Battle of Gods. After everything with Beerus is dealt with, Goku teases Vegeta over his Rage Breaking Point No-Holds-Barred Beatdown on Beerus after he slapped Bulma. After accidentally insulting Bulma over suggesting she'd be slapped again to make Vegeta stronger again, Goku's confronted by Piccolo who realized Goku shouldn't have known that moment unless he had been there the entire time. Turns out he had Instant Transmissioned over there and was watching in an attempt to think of a plan, but couldn't figure one out.