* AntiClimaxBoss:
** [[spoiler: Bermuda, despite being a Cursed Arcobaleno, goes down by Tsuna's new SuperMode in one chapter. Immediately after this, Checker Face reveals himself to be a WellIntentionedExtremist and gives into Tsuna's peace negotiations.]]
** Byakuran despite all the build-up, [[spoiler: especially being a MultiversalConqueror of '''almost every multiverse in existence except the one Tsuna lives in''' and having all the knowledge and strength of those worlds,]] gets defeated swiftly in six chapters that reeks heavily of DeusExMachina.
** The Real Six Funeral Wreaths don't fare any better, considering they were either [[DroppedABridgeOnHim disposed of unceremoniously]] or had a DeusExMachina defeat them.
** Nearly all fights from the final arc feel anticlimatic. Whenever somebody is taking the upperfight, the fight is briefly stopped or simply cancelled.
* ArcFatigue: The Future arc which, at the time of its completion, made up over half of the manga. Was even longer in the anime due to two additional {{filler arc}}s in the middle.
* BadassDecay:
** The only way to explain what happened to Adelheid Suzuki: she went from fighting evenly with Hibari to not being able to land a single blow on him within slightly more than a week. This is especially egregious when you consider that not only did she get a massive power boost from the "Vongola Sin", it was expressly stated that this power would continue to grow over the course of the next seven days.
** Tsuna goes through this in every single arc. He manages to defeat the BigBad from each arc, but in the next one is stomped by the first enemy he faces and feels completely insecure about it.
* BaseBreaker: A few:
** Hibari: Half of the fandom loves him because of his MemeticBadass anti-hero status, the other half hates him, seeing him as a CreatorsPet JerkSue. It doesn't help that we see the other characters have to endure TrainingFromHell and every fight he participates in are [[AntiClimax anticlimactic]].
** Tsuna: Many see his reluctance to fight as a nice change from the cliche action hero. However, many fans are annoyed that he is still a whiny idiot and keeps losing at the beginning of each arc.
* DracoInLeatherPants: Um... close to every single major villain to date?! As one fan made note, to be a villain in this series you must be FAB.
* DudeNotFunny: 5 year old Lambo might come across as annoying, but the comical physical abuse he receives from Reborn is just unwarranted and inappropriate to many.
* DuelingShows: Averted, surprisingly this doesn't have one despite being a popular shonen series. It could be because there's no other series that has the same concept as this one.
* EarWorm: A good number of the songs from the anime, openings endings or character songs can be guilty of becoming this.
* EnsembleDarkhorse:
** Kyoya Hibari is statistically proven. He has always been number one in every poll to date.
** A recent poll has Squalo put in 4th place.
** Fran. His unique, snarky, personality is loved by practically everyone.
** Enma. There's a reason he was the ONLY member of the Simon Family that actually got a relevant role during the Curse of the Rainbow arc.
* EvilIsSexy: Boy is it ever in this series.
* ExpectationLowerer: First shown as being slightly weaker then Squalo, Basil is this for Tsuna, Yamamoto, and basically everyone else.
* FashionVictimVillain: Daemon Spade. Which is sad because for the most part he applied to the EvilIsSexy trope... and then he went and [[spoiler: possessed Mukuro. Now we have ''[[http://www.imagebam.com/image/a0fcae131803947 this]]''.]] Standard fandom response is laughing your ass off.
* FoeYay: [[FoeYay/KatekyoHitmanReborn Now with its very own page!]]
* GrowingTheBeard: By the Varia arc; the Kokuyo arc was the first to be DarkerAndEdgier, but the Varia arc did wonders in world-building and generally having a more engaging plot.
* HarsherInHindsight: Reborn's early interactions with Lambo. Sure, we know how [[SpoiledBrat annoying]] Lambo is, about all that "rivalry" thing and that he's not gonna be killed even by grenades, but once we realize it's an [[spoiler: adult hitman]] beating the living crap out of 5-year old kid... DudeNotFunny.
* HoYay: [[HoYay/KatekyoHitmanReborn Has its own page.]]
* IKnewIt:
** Pretty much what the entire fanbase was thinking when [[spoiler: the Simon Family was revealed to be Big Bad of the Inheritance Ceremony arc.]]
** Quite a few people predicted that [[spoiler: Simon had Earth-based flames]], too.
** Some of the people who also saw the anime predicted Daemon Spade's role in the series in that same arc.
** And also that [[spoiler:Hibari]] is the one who represented Fon in the Representative Battle.
** Almost everyone was betting on [[spoiler: Uncle Kawahira coming back to be revealed as Checker Face.]]
* JumpingTheShark: During the Future Arc.
* LauncherOfAThousandShips:
** Tsuna, oh god, Tsuna.
** Chrome to a degree as well, by virtue of being the [[SmurfettePrinciple only female]] amongst the guardians.
* ItGetsBetter: Around volume eight. [[WhamEpisode Chapter 62]] to be exact.
* MagnificentBastard:
** Reborn.
** [[spoiler: Byakuran]] definitely fits the bill.[[spoiler: In every single one of the multiverses.]]
** With the reveal of who really masterminded the time travel plot, [[spoiler: TYL!Tsuna gets props for putting the kids in significant danger just to motivate his younger self. His own younger self can't believe it was really him.]]
** [[spoiler: [[BigBad Daemon Spade]] managed to successfully pull a GrandTheftMe on [[ManipulativeBastard Mukuro]].]] Lemme just repeat that: [[spoiler: '''He pulled a GrandTheftMe on ''MUKURO''.''']]
* MemeticMolester: Hoo boy, this series has a decent number of them. To wit:
** Mukuro Rokudo's gonna have some ''goddamn'' fun with you. And [[GrandTheftMe wants your body.]]
** [[SlasherSmile Birds]]... just [[GigglingVillain Birds.]] [[SarcasmMode Gotta love]] the creepy old sadists...
** DepravedHomosexual Lussuria of the Varia. Who during his fight with Ryohei expresses blatant [[FoeYay interest]] in him while simultaneously reveling himself to be a necrophiliac.
** Dino's a more arguable case, due to his grin when you see [[http://www.mangahere.com/manga/katekyo_hitman_reborn/v10/c086/19.html this]] first encounter with Hibari as his pupil.
** Glo Xinia. It is heavily implied during his encounter with Chrome that if Mukuro hadn't stepped in when he did, Glo probably would have tried to rape her.
** Spanner's wildly regarded as a pedophile due to his interactions with Tsuna, which included stripping him for no real reason and handcuffing him to his bed. His blushing face (in regards to the X-Burner technically) and sudden HeelFaceTurn don't help.
** [[EvilOverlord Byakuran]] smiles constantly, loves "symbolic flowers", kills off one of KHR's other memetic rapists, and has signature moves where he 'penetrates you'. Oh and let's not forget his image song where he asks you to 'give him your body'. Then there's his blatant obsession with Yuni once she escapes from his grasp. Although there is a good reason for it, the vibes are still there. Not to mention his grabbing of Tsuna from behind and whispering into his ear...
** Julie Katou wants you to know that you have "date plans" with him. And he will help you dress for them~ [[spoiler: Shame this is all due to Daemon Spade possessing him]].
** Daemon Spade's a pedophile that wants your body. ''Nufufu~'' [[spoiler:How ironic that one of the {{Memetic Molester}}s above is a [[GrandTheftMe VICTIM]] for this guy.]]
* {{Moe}}: Tsuna. Oh so much. Chrome too.
* MoralEventHorizon: [[spoiler:Mukuro's utter and rather brutal LackOfEmpathy when fighting with illusions of the Kokuyo Gang raised a few eyebrows among fans considering they're the main source of his PetTheDog moments.]]
* {{Narm}}:
** Despite the clear amount of drama and "OhCrap" moments going on in the most recent chapters of the Inheritance Ceremony arc, the Fandom still laughed its collective ass off at [[spoiler: how Daemon looks in Mukuro's [[http://www.imagebam.com/image/a0fcae131803947 body]].]]
** [[http://www.mangahere.com/manga/katekyo_hitman_reborn/v26/c240/6.html Giant Byakuran head in the sky.]]
** [[CreepyTwins The Bloody Twins]], who were horrifying in the manga, look more like two stoned freaks in the original mugshot in the [[{{Bowdlerize}} anime]].
** Also Bermuda's [[spoiler: [[http://c.mfcdn.net/store/manga/880/TBD-401.0/compressed/v020.jpg adult form]].]] It's hard to take it seriously.
*** And his "[[http://c.mfcdn.net/store/manga/880/TBD-403.0/compressed/o018.jpg 100% Lethal Final Technique]]" [[DoesThisRemindYouOfAnything Do these shapes remind you of anything?]]
* PeripheryDemographic: Did the number of bishies in the story really convince you that this series was ''just'' for guys?
* TheScrappy:
** Longchamp Naito. Near-universally despised by a large percentage of overseas fans due largely to his goofy appearance and rambunctious personality. [[{{Hatedom}} There is a reason he only appeared in the manga...]]
** Also 5 year old Lambo. Most of the fans find his BrattyHalfPint tendencies annoying rather than endearing.
* ShockingSwerve: The real identity of Checker Face is [[spoiler: Kawahira, the Ramen shop owner...[[ChuckCunninghamSyndrome who is that again?]]]]
* TheyWastedAPerfectlyGoodCharacter:
** There were many who were DemotedToExtra in the final arc, such as Ryohei, Lambo, and even Yamamoto and Gokudera. Especially jarring since they had just received brand new Cambio Forma weaponry in the previous arc, which Gokudera and Yamamoto had barely shown off.
** 20YL!Lambo, the [[CharacterDevelopment mature]], [[{{Hunk}} handsome]], and incredibly BadAss future version of 5-year-old Lambo, only ever appears in one chapter. It's justified that he can't show up in the Future Arc due to Lambo not being in possession of his 10-Year Bazooka, but even afterwards it's only 10YL!Lambo that makes a reappearance.
* TheyWastedAPerfectlyGoodPlot:
** The Arcobaleno Arc could've been great, if it wasn't for its premature ending.
** Mukuro and Hibari never got their rematch despite their build up.
* UncannyValley: [[spoiler: Bermuda's]] true form resembles a doll whose proportions are too unbalanced. His eyes are too large for his baby like face, has a nose that is practically nonexistent and has the arms of a bodybuilder attached to an adolescent body.
* UnfortunateImplications:
** Chrome is the strongest female in the series; a girl who lacks organs, depends on a man to help her fight, and finds herself helpless and/or captured in almost every single battle. She is also the only girl that has been fighting the bad guys in the last two arcs.
** The poor treatment female characters get has been noticed by several people. Kyoko and Haru are probably the most abused. Whenever the main characters are dealing with a serious conflict, Haru and Kyoko are not even told about it and have stay at home doing things for the boys (alongside I-Pin and Bianchi, even though they're both ''professional assassins''). The thing is that this never changes so many (even their fans) saw their absence from the Simon arc onwards positive since they would not be used so much again.
** Adelheid at least started out to be what looked like the first genuine ActionGirl {{Badass}} of the series. People were even describing her as the {{Foil}} to BaseBreaker Hibari during her shining moments. Sadly, it all went away the moment she was forced into the background to rot for the rest of the manga after the Daemon Spade reveal.
** Lussuria's character. He's the only cast member who's explicitly homosexual... and made moves on an underage boy while revealing himself to be a necrophiliac.
* {{Wangst}}: A strange case. Tsuna's life is supposed to have gotten better after meeting Reborn, but Byakuran tortures him in the Future arc by saying how much his life sucked in that arc. Ironically, he is kind of right considering how at the beginning Tsuna was exasperated with the idea of not going home while his friends were trying to stay calm about it.
* TheWoobie:
** Gokudera, especially when you learn about his past.
** Chrome also due to the hell she goes through. Her parents abandoned her to die, half her organs are missing, she's constantly belittled, and most recently [[spoiler: she's been [[HypnotizethePrincess hypnotized]] and tortured by D.Spade purely to push Mukuro's BerserkButton.]]
** [[spoiler: 20YL!Lambo, particularly when you realize, thanks to Byakuran, exactly what kind of [[BadFuture future]] he has to return to.]]
** Yuni, and by extension Luche herself. Luche was BlessedWithSuck, received the less-than-beneficial end of the CursedWithAwesome stick shared by her other partners, and worse yet has to pass that on to all her future descendents.
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