History Fanfic / CatchYourBreath

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!!''A Ninja's Guide to Gotham'' contains examples of:
[[folder:A Ninja's Guide to Gotham]]
* AnArmAndALeg: Hayate cuts the arm off a Zetsu clone in chapter 18 offscreen, only to throw it out the window after the owner once Kei defenestrates it.
* AngerBornOfWorry: The first time Jason catches Hayate following him during a job, he starts shouting at him and orders him out of the building. Hayate is unfazed by the scolding and finally forces Jason to realize that, if he can't actually rely on Hayate to keep himself safe in the apartment, then Jason needs to supervise him directly.
* AnimalEyeSpy: [[PestController Aburame clan members]] can't do this normally, but Shimika manages to look through all the eyes of the kikai insects sent to infiltrate the League of Assassins. It took a lot of time to develop the ability, even with multiple fūinjutsu masters, and it causes a PowerStrainBlackout within minutes.
* AssassinOutclassin: The League of Assassins, as it turns out, has a somewhat spotty record against the Batfamily, never mind superpowered magic ninjas from another world.
** Kei, as a PersonOfMassDestruction, is only inconvenienced by League operatives because she wants to observe Batman's ThouShaltNotKill rule while in Gotham. The main threat posed by the assassins is less of a chance that she'd lose to them in a fight and more the idea that their TranquillizerDart weapons might contain something dangerous enough to drive her berserk in a populated area.
** After being informed that the League of Assassins might be after Hayate, Jason's narration notes that he's been dealing with stray assassins by dropping them headfirst off buildings.
** Hayate is more than capable of fighting off League assassins even three-on-one. It's later clarified that he never attacks them head-on, preferring instead to get the jump on them with an AttackHello.
* BigBrotherInstinct: Centered on the same kid, even:
** On one hand, Kei’s natural drive to protect Hayate has made her more moody and desperate the longer she’s separated from him. Seeing as Kei is a jinchūriki, her long fuse is attached to a much larger bomb than most people’s.
** This trope crosses with Jason’s WouldNotHurtAChild policy upon his and Hayate’s first meeting, which results in Red Hood taking an injured young ninja under his wing.
** In return, Hayate thinks they’re both overprotective. [[UsefulNotes/JapaneseSiblingTerminology But he does call them “Oneesan” and “Aniki” in response]], showing that he appreciates them.
* BigDamnReunion: Kei and Hayate finally see each other again in chapter 12, after finishing off the Fearsome Hand of Four, and they bear hug each other immediately. Because it's from Kei's point of view, all other participants in the scene vanish by comparison to the emotional moment.
* CantDefaultToMurder: Unsurprisingly for a shinobi of her era and power level, Kei has a body count and isn't especially concerned about adding to it while on missions. While in Gotham, however, Kei does her best to avoid killing anyone directly, because she realizes that leaving a trail of bodies around the city would draw undue attention and probably get her on Batman's bad side. This doesn't stop the League of Assassins and her allies in Konoha from racking up killcounts behind her back, for different reasons.
* ChildSoldiers: Discussed and pulled apart by various characters’ stances on the topic.
** Kei (16) and Hayate (14) are both this, being a special jōnin and a chūnin respectively. Of the two of them, Hayate is much more upbeat about it, because he has no other frame of reference.
** Jason hates this concept down to his bones, thinking of the entire teen vigilante lifestyle as what got him killed in the first place. And on top of that, everyone he knew seemed to just carry on without learning anything from his death.
** The Bats in general are deeply disturbed by the implications of a couple of teenagers being multi-year war veterans, and Tim's research indicates that even in their world's version of pre-modern Japan, the age of majority was never lower than fifteen.
* ConditionedToAcceptHorror: Jason is stunned by what information Hayate offers about his life thus far, and is sure that the society he came from is a League of Assassins-tier abomination. Every time Hayate easily accepts Jason’s violent tactics, it makes him more and more uncomfortable.
* CoupDeGrace: Though Kei leaves defeated League assassins alive once they're down and restrained, Jiraiya orders Shimika to kill them via the [[MothMenace chakra-eating butterflies]] after Kei leaves the building.
* CultureClash:
** Most commonly exemplified by the conversations between Jason and Hayate in the former’s apartment. Konoha is ''very'' different from Gotham.
** Tim and Hayate’s first interaction is almost entirely at cross-purposes. While Hayate is content with the changes Jason has made to Crime Alley and doesn’t mind the violent enforcement incidents (including decapitation) because he’s from a barely-not-feudal society, Tim is worried that Red Hood is inducting kids into his gang as he expands his influence.
** Kei is very aware that leaving a trail of bodies in Gotham is a bad idea, even if her commanding officers would view any deaths as self-defense given her circumstances. As a result, she spends most of her time avoiding conflict anywhere she can to remove the chance of something going wrong. Hayate is…not so careful, because he is immediately dropped into a fight and doesn’t know anything about Gotham.
** In a much less dramatic example, Kei and Tim briefly discuss preferred pronouns and the author points out in a note that Kei transmigrated before gay marriage was even legal in the US.
* CurbStompBattle:
** Jason's first appearance shows exactly how outgunned the standard Gotham goon is in a fight with the Red Hood, taking out more than twenty armed opponents within ten minutes. He also serves as a brick wall for the League of Assassins' operations in his territory, killing their agents for incursions.
** Every time Kei runs into the League of Assassins, one of these ensues. She refuses to kill them, despite their persistence, because leaving a trail of bodies in Gotham is an excellent way to get on society's bad side. Her issue is [[ScarilyCompetentTracker their tracking skills]], which means she has no time to rest between attacks unless she can find a way to lose them. It takes until she cuts a deal with Red Hood and then the Bats before she can effectively find a place to hide.
** Hayate describes his own encounters with the League of Assassins like this as well. Later, it's revealed that he attacks from under an invisibility genjutsu and [[ShockAndAwe shocks them unconscious]].
* DecapitationPresentation: Offscreen, Jason tracks down the lieutenants of the biggest drug-running operations in Gotham, kills all of them, and tosses the duffel bag full of severed heads onto the table at the next big meeting to establish dominance. Other characters mention hearing about it and wonder what kind of person would go that far.
* DestinationDefenestration: Once provoked by a group of Zetsu, Kei kicks two of them out of the high-rise apartment window. Because Zetsu are more durable than humans, even launching them with enough force to ''hit the opposite building'' doesn't deter them for long.
* DramaticIrony: Every single one of the POV characters is missing some vital information that would otherwise change their decisions. Much entertainment is had from watching them stumble toward or away from the correct conclusions.
** Kei has no idea that Hayate landed in close proximity to a gang fight and was subsequently picked up by Jason. He's been living in Crime Alley since then, which is one of the areas Kei hasn't searched thoroughly because of Red Hood's presence.
** Hayate doesn't have the sensor range to be able to find Kei in such a large city without her going out of her way to enter a Tailed Beast transformation, and lacks the personal history and cultural context to make fully informed decisions about how he behaves in Gotham. As a result, he tends to stay mostly in Crime Alley, which is one part of the city that Kei actively avoids.
** Jason doesn't know that Kei and Hayate are related when he meets each of them, or that they're looking for each other. He also doesn't know that Hayate has been noticed by the local vigilante population under the name "Suzaku," or that Hayate is TheEmpath and reading his emotions all the time.
** Tim and Dick don't know that Kei's whole purpose to find Hayate and stay out of trouble, primarily because she refuses to tell them anything directly. They also assume that "Suzaku" is part of Red Hood's gang, as opposed to being just a kid TrappedInAnotherWorld that Jason is trying to look after on the side.
** Back home in Konoha, none of the shinobi realize that they're not supposed to be killing people in Gotham until Kei writes a note that they can read through the crystal ball. They also don't know that there's any preexisting relationship between the Bats and the League of Assassins that might complicate their interactions.
* DynamicEntry: Used a couple of different times.
** Hayate sneaks up on and lays into the three assassins cornering Spoiler, defeating them inside of twenty seconds.
** Kei's GroundShatteringLanding doubles as her first attack in the fight with the Fearsome Hand of Four, smashing the biggest member of the quartet into a crater on impact. The fight doesn't last very long after that.
* EliteMook: The Fearsome Hand of Four serve as this, putting Red Hood and Batman on the back foot unlike all of their other opponents thus far. This does not save them when Kei arrives, taking down the two remaining members of the group in seconds.
* EveryoneHasStandards:
** Kei is aware she could get funding by overpowering almost anyone and just taking their stuff, she decides against going after people who are treated as BeneathNotice by the authorities. Instead, she comes up with her MuggingTheMonster scheme below.
** Jason, as Red Hood, is running a "moral" drug empire by imposing restrictions against selling to children and limiting violence against civilians in his territory. Hayate sees evidence of this in the formation of an informal neighborhood watch, signified by subtle red accessories on citizens allied with Red Hood, and notes that sex workers in the area are actively protected. His policies are, unsurprisingly, enforced at gunpoint.
** Nobody likes the Joker. At all.
* FightingFingerprint: Unbeknownst to either Batman or Red Hood, Hayate realizes they've trained together just by watching [[BackToBackBadasses the way they fight]] against the Fearsome Hand of Four.
* FishOutOfWater: Hayate, who was raised entirely in Konoha and doesn’t know how guns, cars, or digital technology work. Luckily, he runs into Jason in the first ten minutes.
* {{Foil}}: All over the place.
** Kei and Hayate’s circumstances are constantly contrasted. While Kei landed in Gotham with some idea of how to survive in a modern city, she’s beset by circumstantial difficulties and the League of Assassins. Hayate, meanwhile, was immediately scooped up by an up-and-coming mob boss who WouldNotHurtAChild and is on vacation by comparison.
** Hayate and Tim are respectively a NinjaBrat and a TeenGenius vigilante, and they have very different moral standards despite being nearly the same age. Tim is appalled by Red Hood’s rise to power, while Hayate approves of or at least accepts his methods.
** Kei and Jason are both dangerous teenaged fighters without a no-kill policy, and their protective instincts are focused on the same kid. Kei is a PersonOfMassDestruction, but she chooses to fight nonlethally in Gotham to keep a lower profile. Jason, meanwhile, is a BadassNormal putting together enough resources to become a crime lord to rival Black Mask and doesn’t especially care how many bodies are left in his wake. Both of them also have contrasting relationships with the League of Assassins, with Kei as a target and Jason having been trained by them.
* TheFourGods:
** Kei picks the mask name “Genbu” as an inside joke because she’s wearing mostly black clothes and an ANBU mask designed to look like Isobu’s face.
** Hayate accidentally chooses the rogue identity “Suzaku” as an on-the-spot option while talking to Robin, unaware of his sister’s decision. It serves as one of many connecting elements between them.
* TheGlomp: When Kei and Hayate finally meet again in person, Hayate executes a flying tackle-hug that Kei has to work to turn into a standard bear hug.
* HydroElectroCombo: Kei and Hayate's primary nature transformations form this dynamic.
* InternalReveal:
** Chapter 6: After almost three weeks of silence on the topic, Hayate explains what a jinchūriki is to Jason.
** Chapter 10: Kei finds out that Hayate, as Suzaku, is a known associate of Red Hood.
** Chapter 11: With encouragement from Stephanie, Kei finally explains the situation with her brother and her jinchūriki status to them, clarifies the threat represented by the League of Assassins, and helps Tim and Steph figure out some of the magical strangeness happening in Gotham. Kei also admits that she and Hayate are TrappedInAnotherWorld and just want to go home.
** Chapter 12: Hayate finds out that Kei's bilingual right at the end of the chapter, which is tied to an S-rank classified secret; namely, that Kei is a transmigrator.
** Chapter 14: After some pressure from Kei, Hayate transforms into an undisguised Red Hood, and Dick's reaction shows that he instantly recognizes his dead brother's face.
** Chapter 15: By watching the footage from the previous chapter and testing blood leftover from the fight with the Fearsome Hand of Four, Batfamily confirm that the mysterious Red Hood is actually the resurrected Jason Todd.
** Chapter 18: Kei and Hayate finally learn that Konoha is capable of delivering packages to their apartment through space-time manipulation, and that the League of Assassins has Zetsu clones. They try to share this with the Bats as soon as they can.
* ItSeemedTrivial:
** While Hayate is aware that Jason has seriously conflicted feelings about the Batfamily thanks to his status as TheEmpath, he hasn’t been able to pry the reason out of him. As a result, he accidentally explains a fair bit about Red Hood’s personality and policy to Tim, after catching him attempting a preliminary investigation into Crime Alley.
** Initially, Gotham's heroes are pretty unsure of whether Genbu (Kei) and Suzaku (Hayate) are related rogues, and so they don't mention them to each other. This goes out the window when Tim runs their DNA through the Batcomputer and finds out that they're siblings.
* KillingIntent: Despite being {{Badass Normal}}s, the Bats are actually fairly sensitive to this, which lets them easily detect when Kei is feeling combative or when [[AnimalisticAbomination Isobu]] is acting up.
* LanguageBarrier: Hayate only speaks Japanese with some loanwords thrown in, limiting the number of characters he can easily interact with. Luckily, Jason’s a Bat-trained vigilante, and that includes foreign languages. Kei, meanwhile, is fully bilingual with a strong accent, so she doesn't have to deal with this.
** Hayate later works around this problem through technology when meeting Robin and Spoiler, though he does accidentally fry the former's gauntlet computer after their first encounter.
** It's noted that when watching the footage of Dick interviewing Hayate and Kei, Bruce has to correct the auto-generated subtitles for the sake of the official record.
* LockedOutOfTheLoop: Multiple characters are keeping secrets that can cause trouble down the line, or would have cut much of their problems short.
** Kei doesn’t trust anyone in Gotham, so she avoids giving Batman, Nightwing, or Robin much information about who she is or what her motivations are. She only seeks them out when Red Hood specifically pays her to and when she’s already worn down by being constantly pursued by Ra’s Al Ghul’s assassins. Kei also knows precisely who the mysterious Red Hood is, and has no intention of revealing that information to the Batclan (whose identities she also knows). She only has the information because she’s a transmigrator, which she can’t explain.
** Tim, after meeting both Kei and Hayate, works out quickly that they’re related. Unfortunately, he also learns that one or both of them murdered two gangsters a few weeks ago and knows the latter is basically working for the Red Hood. As a result, he avoids mentioning Hayate’s activities to Kei. Similiarly, Dick, having met Kei at her cagiest, decides against mentioning “Suzaku” to her in case it stresses her out more. Not long afterward, Tim’s investigation reveals that Red Hood’s smallest lackey is her brother.
*** Kei finds out that the Bats knew about her brother in chapter 10, and narrowly retains control of her temper as one of her most important buttons is accidentally pressed.
** Jason tries to hide his criminal dealings from Hayate, but quickly discovers that Hayate is both aware of how gangs work and can escape Jason’s security measures whenever he feels like it, which lets him roam Gotham at will. That said, he doesn’t know Jason’s real name, despite living in his apartment for the better part of a month.
* MassOhCrap: Every Konoha ninja in the monitor room upon realizing that their investigation of the League of Assassins has uncovered [[HumanoidAbomination a disguised White Zetsu]].
* McNinja: Kei spitefully calls the League of Assassins this by name, frustrated with their constant pursuit.
* MilesToGoBeforeISleep: Hayate worries more that Jason is passively suicidal than about any of the criminal empire stuff. Jason's narration confirms that he has ''no'' plans that extend past his confrontation with the Joker and Batman, and thoughts about longer-term goals tend to get reflexively shut down.
* MissedHimByThatMuch: Kei and Hayate's arrival in Gotham separated them. Both of them repeatedly run into people who know about the opposite sibling, but for a long time aren't able to get information or connect enough dots to reunite.
* MobWar: Ongoing between Black Mask and Red Hood. Kei and Hayate both end up on the wrong end of gang-related shootouts on as early as their first night in Gotham, though only Hayate is injured.
* MoralityPet: After realizing that he can’t allow an injured metahuman to disappear into [[DepartmentOfChildDisservices Gotham's excuse for a social services system]], Jason takes Hayate under his wing as this. He is extremely aware this choice is throwing a monkey wrench into his plans and his ability to execute them, and Hayate's actions are personally causing him a lot of stress, but refuses to go back on it.
* MothMenace: The Gotham characters are understandably skeptical that an incursion of black-and-white butterflies could cause that much damage on their own. As Kei explains, however, they can be used to devour the LifeEnergy of a target or targeted area, and she soon learns that they performed a predatory CoupDeGrace on the assassins who initially survived the fight in chapter 10.
* MuggingTheMonster: Invoked and exploited. Kei acquires funds by using Transformation Jutsu to disguise herself as an easy target in some of the worst neighborhoods in Gotham, then overpowers the would-be muggers and takes their cash. But, because of TechnologyMarchesOn, she’s unable to make use of any cards she finds, which is where the majority of most people’s money really is.
* OneManArmy:
** Hayate notes that one of Jason’s tactics for rooting out rival criminal enterprises is “kick down the front door and shoot them all to death,” and his very first fight has him winning a twenty-on-one shootout without taking a hit on anything but his armor.
** Kei is also this, but no one wants her to reach the point where she has to demonstrate it.
* PersonOfMassDestruction: Kei, which is even more dangerous in a city with as many people as Gotham. The only person Hayate tells about this is Jason, who has MobWar to manage and a ResurrectionRevenge plot to carry out. It takes until Kei hits her personal boiling point for her to actually explain this to the Bats.
* PoorCommunicationKills: Almost every character is keeping secrets from the others. Usually on purpose, but sometimes they just don’t communicate well.
** Kei accidentally makes both Tim and Dick think that she has it out for all other ninjas by being ominously cryptic. Fighting League assassins and occasional bursts of undirected KillingIntent don’t help her case. Kei also rigs pieces of Isobu-generated coral with his chakra, in an attempt to throw off the League of Assassins' tracking methods, which then almost gets Steph killed when she picks one up in the middle of her patrol.
** Jason runs into and hires “Genbu” (Kei in a mask) to distract the Bats and is only told about an hour afterward that she’s Hayate’s missing sister, accidentally squandering the opportunity to reunite them.
** In an effort to avert this going forward, Stephanie and Tim visit Kei and hash out the major concerns of the situation in Gotham over a late-night snack.
** Multiple characters (particularly Steph, Tim, and Jason) note that Kei has a bad habit of lying by omission as a strategy for avoiding conflict, so when Tim attempts to confront her about the holes in her story, he has a hard time believing what she says even when she's trying to tell him about [[StealthyMook Zetsu clones]].
* RageBreakingPoint: After spending enough time in Gotham, Kei suspects the whole goal of the League of Assassins' harrassment campaign is to [[InvokedTrope push her until she snaps and kills someone]], preferably in front of the Bats.
* RecklessSidekick: Jason sees Hayate as an aspiring example, and it scares the hell out of him. He repeatedly remarks in his narration that he doesn't think Hayate has an ounce of sense and that he'll get hurt or killed at ''some'' point with all the sneaking around. In fact, this is a SubvertedTrope because Hayate is a competent shinobi in his own right. His POV chapters reveal that he takes numerous precautions to avoid detection or conflict even within Red Hood's territory, and doesn't fight street crime like a vigilante would. He even gives up a chance to potentially reunite with his sister when he suspects the opportunity ''could'' turn into a trap he can't escape.
** Jason eventually caves to Hayate's demands to follow him around, but only if he agrees to stay out of sight and avoid trouble. He figures that if Hayate's going to be running around Gotham regardless, it may as well happen while Jason is around to mitigate the risks. He seems entirely unaware that Bruce came to the exact same conclusion regarding the first Robin's nighttime forays into Gotham, as a part of Dick Grayson's origin story.
* RetroUniverse: While Gotham's technology is on par with the present day, allowing for things like smartphones and ubiquitous internet usage by the characters, the ''Naruto'' universe is unquestionably this. Holding a VHS tape from Konoha that contains video evidence of the infiltration of the League of Assassins base, Kei has no choice but to sigh over the incompatible data formats.
* ScarilyCompetentTracker: The League of Assassins has some method of finding Kei that she theorizes is related to Isobu's chakra. Notably, they either can't find Hayate with the same efficiency, and most of their agents who do end up in his proximity are dealt with by [[VillainKiller Red Hood]].
* SecretIdentity: Several, since Gotham’s one of the most famous superhero story settings of all time. Besides the Batfamily, Kei chooses the vigilante moniker “Genbu” and Hayate (entirely coincidentally) chooses “Suzaku.”
* SecretSecretKeeper: Kei already knows the Batfamily’s identities due to being a transmigrator, but isn’t interested in sharing the information.
* SlaveryIsASpecialKindOfEvil: Hayate explains to Jason that he has absolutely no problem with human traffickers being killed, because Konoha’s policy is to execute them on the spot. Jason, who was trying to explain [[SuperhumanTrafficking the reasons why]] he didn’t want Hayate following him at night, is mostly disturbed by his total nonchalance.
* SmokeOut:
** Kei has a version of this in the form of the Hidden Mist ninjutsu, which doubles as a replacement for her usual sensing technique while in Gotham. It's also a tactic that's immediately recognizable to other shinobi who've seen her fight, like Hayate.
** A tactic habitually employed by the Bats, mainly in the form of smoke bombs of various formulations. Jason uses one to break off from his conversation with Bruce after defeating the Fearsome Hand of Four, leaving Hayate behind with Kei.
* SpottingTheThread: There are a number of details that connect Kei and Hayate’s SecretIdentities, mostly because they don’t work very hard to hide them. Hayate doesn’t even know that masked identities are a thing until Jason explains.
** Jason notes that “Spike” wears the same kind of kunai holster that Hayate does, and asks about it. Hayate immediately identifies the other ninja as Kei once Jason starts elaborating on their encounter.
** Tim also notices that “Genbu” and “Suzaku” share equipment loadouts, down to the katana each of them wear on their hips. Which is a problem, because kunai also leave distinct wounds and indicates one of them killed two people. He's also the first to realize that Kei knows more about the Red Hood situation than she's been letting on.
* StealthyMook: The League of Assassins is this, by the story's standards. As are the Zetsu clones that show up in their ranks, but more so.
* SwitchingPOV: Aside from Kei's usual focus, other POV characters include Hayate, Jason, Dick, Tim, Steph, and Kakashi.
* TakingTheBullet:
** With an energy weapon instead of bullets, but Jason reflexively does this for Bruce during the fight against the Fearsome Hand of Four. His body armor turns out to be tough enough to let him survive, albeit a bit stunned. Tim notes afterward that because it's so hard to predict what effect an energy blast might have in a [[FantasyKitchenSink world like theirs]], it's even riskier than just being shot by an actual bullet.
** Knowing that [[PersonOfMassDestruction Kei]] is being targeted deliberately, Tim shoves her out of the way of one of the League of Assassins' dart guns and accidentally takes the shot instead.
* TastesLikeFriendship:
** Jason quickly takes this tack with Hayate, reasoning that he has to feed the kid. Later on, he notes that Hayate reciprocates by making him post-patrol meals and is a little exasperated that the kid keeps ruining his sleep schedule over it.
** Kei attempts this with Tim, but frames it as a thank-you for helping her move into a safehouse. Tim doesn’t really notice the overture at the time. It takes a few more chapters before she finally succeeds when Steph accompanies Tim to the next meeting, with everyone chowing down on pizza bagels and soda while they properly hash out their situation.
* TeamMercyVsTeamMurder: Comes up a fair amount, because shinobi are mostly on Team Murder by default. Kei doesn't avoid killing people because she is a particularly merciful person; rather, she wants to avoid negative attention from locals.
* TranquillizerDart: Rather than normal guns or some kind of exotic effect, Kei notes that the League of Assassins seems to favor this weapon type when dealing with her. Whatever is in them is clearly nasty; one of its known components is [[SupernaturalFearInducer Fear Toxin]].
** InstantSedation: When Tim is hit with a drugged dart meant for Kei, both of them immediately realize the dose is ''way too high'' because of how quickly he succumbs.
** OneDoseFitsAll: Averted. Kei's aware that any compound designed to bring down someone like her is not suited for usage on normal humans. Due to the way even normal sedative dosages are based on body mass and metabolism, an assassin accidentally hit by three full darts overdoses and dies offscreen.
* TrappedInAnotherWorld: What this story is from Kei and Hayate’s perspective. Given that both Gotham and Konoha are extremely weird from the other’s perspective, it’s a fair enough read.
* WalkingTechbane: Hayate has a brush with this trope. While he adapts quickly to his phone when given one, his primary nature transformation is [[ShockAndAwe Lightning Release]]. As a result, a bit of carelessness on his part fries everything electronic on Tim's Robin costume at the end of their first meeting.
* WeirdnessSearchAndRescue: Since Kei and Hayate are important to many people in Konoha’s upper administration personally and professionally, the village’s interludes show them working out how to be this.
* WhiteMaskOfDoom: Kei’s vigilante guise consists of one of these worn over her face, which she admits is just an art project everyone is now taking too seriously. She still considers it more effective a disguise than the classic Robin DominoMask. This actually ends up working against her and Hayate reuniting quickly, because otherwise their StrongFamilyResemblance is obvious.
* WouldNotHurtAChild: Jason’s ironclad policy within his territory, which is the main difference between his gang’s behavior before and after his takeover. He’s furious at the idea of ChildSoldiers and absolutely refuses to let Hayate follow him around as a sidekick. It’s also what gets him stuck looking after Hayate in the first place, because he’s unwilling to put Hayate into the hands of any of the corrupt authorities in the city.
* WretchedHive: Kei's opinion of Gotham, due primarily to frustration. The city’s aura of despair and gloom interferes with her SupernaturalSensitivity and gives her sensory overload headaches that require either Isobu’s chakra or a lot of painkillers to counteract. Most of the money she acquires is from mugging people who clearly planned to rob her first, and the social services and police in the city are untrustworthy from her perspective. Also, every single time she’s gone out, someone’s been shooting up the place.
** If there’s one place in Gotham that exemplifies this, it’s Crime Alley/Park Row, the crime-riddled neighborhood where the Waynes were gunned down decades ago. Under Jason’s new management, Hayate notes that it’s actually improving.
* WrongAssumption:
** Due to Kei’s costume choices, Nightwing and Robin assume she’s a new vigilante or a new rogue in town. In truth, Kei is TrappedInAnotherWorld and looking for her missing brother, but doesn’t trust any of the other characters enough to ask for help for a long time. The costume was a whim and now she’s too far into the game to turn back.
** Jason, who is familiar with the League of Assassins, figures that Hayate is a product of another secret murder-conspiracy cult he just hasn’t heard of. He’s wrong, but it’s reasonable based on what he knows.
** Everyone who meets Kei and Hayate reasonably afigures they’re standard Earth metahumans, at least until Tim’s DNA analysis comes back and reveals [[TouchedByVorlons nonhuman heritage]] of an [[{{Characters/NarutoOtsutsukiClan}} unknown origin]]. When Tim explains this to Kei later on, she's in no mood to even contemplate the idea of aliens and just grumbles that [[FantasticallyIndifferent this might as well be a real thing]].
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** Multiple characters (particularly Steph, Tim, and Jason) note that Kei has a bad habit of lying by omission as a strategy for avoiding conflict, so when Tim attempts to confront her abou the holes in her story, he has a hard time believing what she says even when she's trying to tell him about [[StealthyMook Zetsu clones]].

* OneManArmy: Hayate notes that one of Jason’s tactics for rooting out rival criminal enterprises is “kick down the front door and shoot them all to death,” and his very first fight has him winning a twenty-on-one shootout without taking a hit on anything but his armor.

* PersonOfMassDestruction: Kei, which is even more dangerous in a city with as many people as Gotham. Unfortunately, Kei refuses to mention this to the Bats and the only person Hayate tells about this is Jason, who has MobWar to manage and a ResurrectionRevenge plot to carry out.

** Jason's first appearance shows exactly how outgunned the standard Gotham goon is in a fight with the Red Hood, taking out more than twenty armed opponents within ten minutes.

** Hayate describes his own encounters with the League of Assassins like this as well; later, it's revealed that he attacks from under an invisibility genjutsu and [[ShockAndAwe shocks them unconscious]].

** Chapter 18: Kei and Hayate finally learn that Konoha is capable of delivering packages to their apartment through space-time manipulation, and that the League of Assassins has Zetsu clones. They try to share this with the Bats as soon as is reasonable.

** Kei has a version of this in the form of the Hidden Mist ninjutsu, which doubles as a replacement for her usual sensing technique while in Gotham. It's a tactic that's immediately recognizable to other shinobi who've seen her fight, like Hayate.

** Kei (16) and Hayate (14) are both this, being a special jōnin and a chūnin respectively. Of the two of them, Hayate is much more upbeat about it because he has no other frame of reference for his life.

** Every time Kei runs into the League of Assassins, one of these ensues. She refuses to kill them, despite their persistence, because leaving a trail of bodies in Gotham is an excellent way to get on society's bad side. Her issue is their tracking skills, which means she has no time to rest between attacks until she can find a way to lose them. It takes until she cuts a deal with Red Hood and then the Bats before she can fully lose them.

** Hayate doesn't have the sensor range to be able to find Kei in such a large city without her sending up a deliberate flare, and lacks the personal history and cultural context to make fully informed decisions about how he behaves in Gotham. As a result, he tends to stay mostly in Crime Alley, which is one part of the city that Kei actively avoids.

** Kei picks the mask name “Genbu” as an inside joke because she’s wearing mostly black and an ANBU mask designed to look like Isobu’s face.

* TakingTheBullet: With an energy weapon instead of bullets, but Jason reflexively does this for Bruce during the fight against the Fearsome Hand of Four. His body armor turns out to be tough enough to let him survive, albeit a bit stunned. Tim notes afterward that because it's so hard to predict what effect an energy blast might have in a [[FantasyKitchenSink world like theirs]], it's even riskier than just being shot by an actual bullet.

* TranquillizerDart: Rather than guns or some kind of exotic effect, Kei notes that the League of Assassins seems to favor this weapon type when dealing with her. Due to the way dosages are based on body mass and metabolism, an assassin hit by three full darts' worth of drug cocktails actually overdoses and dies offscreen.
* WeirdnessSearchAndRescue: Since Kei and Hayate are important to many people in Konoha’s upper administration personally and professionally, the village’s interlude shows them working out how to be this.

** Everyone who meets Kei and Hayate reasonably afigures they’re standard metahumans, at least until Tim’s DNA analysis comes back and reveals [[TouchedByVorlons nonhuman heritage]] of an [[{{Characters/NarutoOtsutsukiClan}} unknown origin]]. When Tim explains this to Kei later on, she's in no mood to even contemplate the idea of aliens and just grumbles that [[FantasticallyIndifferent this might as well be a real thing]].

* AngerBornOfWorry: The first time Jason catches Hayate following him during a job, he starts shouting at him and orders him out of the building. Hayate, unsurprisingly, is unfazed.

** Chapter 15: By watching the footage from the previous chapter and testing blood leftover from the fight with the Fearsome Hand of Four, Batfamily learn that the mysterious Red Hood is actually the resurrected Jason Todd.

* LanguageBarrier: Hayate only speaks Japanese with some loanwords thrown in, sharply limiting the number of characters he can easily interact with. Luckily, Jason’s a Bat-trained vigilante, and that includes foreign languages. Kei, meanwhile, is fully bilingual with a strong accent, so she doesn't have to deal with this.
** Hayate later works around this problem through technology when meeting Robin and Spoiler, though he does accidentally fry the former's gauntlet computer afterward.

* WeirdnessSearchAndRescue: Since Kei and Hayate are important to many people in Konoha’s upper administration, the village’s interlude shows them working out how to be this.

** A tactic habitually by the Bat-Family, mainly in the form of smoke bombs of various formulations. Jason uses one to break off from his conversation with Bruce after defeating the Fearsome Hand of Four, leaving Hayate behind with Kei.

** Tim also notices that “Genbu” and “Suzaku” share equipment loadouts, down to the katana each of them wear on their hips. Which is a problem, because kunai also leave distinct wounds and indicates one of them killed two people.

* RecklessSidekick: Jason perceives Hayate as an aspiring example, and it scares the hell out of him. He repeatedly remarks in his narration that he doesn't think Hayate has an ounce of sense and that he'll get hurt or killed at ''some'' point with all the sneaking around. In fact, this is a SubvertedTrope because Hayate is a competent shinobi in his own right. His POV chapters reveal that he takes numerous precautions to avoid detection or conflict even within Red Hood's territory, and doesn't fight street crime like a vigilante would. He even gives up a chance to potentially reunite with his sister when he suspects the opportunity ''could'' turn into a trap he can't escape.
** Jason eventually caves to Hayate's demands to follow him around, but only if he agrees to stay out of sight and avoid trouble. He figures that if Hayate's going to be running around Gotham regardless, it may as well happen while Jason is around to mitigate the risks.

** Kei has a version of this in the form of the Hidden Mist ninjutsu, which doubles as a replacement for her usual sensing technique while in Gotham. It's a tactic that's immediately recognizable to other shinobi, like Hayate.

* TranquillizerDart: Rather than guns or some kind of exotic effect weapon, Kei notes that the League of Assassins seems to favor this weapon type when dealing with her. Due to the way dosages are based on body mass and metabolism, an assassin hit by three full darts' worth of drug cocktails actually overdoses and dies offscreen.

* WhiteMaskOfDoom: Kei’s vigilante guise consists of one of these worn over her face, which she admits is just an art project everyone is now taking too seriously. She still considers it more effective a disguise than the classic Robin DominoMask.

** Due to Kei’s costume choices, they assume she’s a new vigilante or a new rogue in town. In truth, Kei is TrappedInAnotherWorld and looking for her missing brother, but doesn’t trust any of the other characters enough to ask for help. The costume was a whim and now she’s too far into the game to turn back.

** Everyone who meets Kei and Hayate reasonably assumes they’re standard metahumans, at least until Tim’s DNA analysis comes back and reveals [[TouchedByVorlons nonhuman heritage]] of an [[{{Characters/NarutoOtsutsukiClan}} unknown origin]]. When Tim explains this to Kei later on, she's in no mood to even contemplate the idea of aliens and just grumbles that [[FantasticallyIndifferent this might as well be a real thing]].

* CultureClash: Most commonly exemplified by the conversations between Jason and Hayate in the former’s apartment.

** Jason doesn't know that Kei and Hayate are related when he meets each of them, or that they're looking for each other. He also doesn't know that Hayate has been noticed by the local vigilante population under the name "Suzaku."

* SlaveryIsASpecialKindOfEvil: Hayate explains to Jason that he has absolutely no problem with human traffickers being killed, because Konoha’s policy is to execute them on the spot. Jason, who was trying to explain [[SuperhumanTrafficking why]] he didn’t want Hayate following him at night, is mostly disturbed by his total nonchalance.

** Kei has a version of this in the form of the Hidden Mist ninjutsu, which doubles as a replacement for her usual sensing technique while in Gotham. It's a tactic that's immediately recognizable to people who know her, like Hayate.

** Everyone who meets Kei and Hayate reasonably assumes they’re standard metahumans, at least until Tim’s DNA analysis comes back and reveals [[TouchedByVorlons nonhuman heritage]] of an [[{{Characters/NarutoOtsutsukiClan unknown origin]]. When Tim explains this to Kei later on, she's in no mood to even contemplate the idea of aliens and just grumbles that [[FantasticallyIndifferent this might as well be a real thing]].

** Chapter 12: Hayate finds out that Kei's bilingual right at the end of the chapter, which is tied to an S-rank classified secret: that Kei is a transmigrator.

* MissedHimByThatMuch: Kei and Hayate's arrival in Gotham separated them. Much of the story from that point onward is both of them repeatedly running into people who know about the other sibling, but not being able to get information or connect enough dots to reunite.

** Jason eventually caves to Hayate's demands to follow him around, but only if he agrees to stay out of sight and avoid trouble. He figures that if Hayate's going to be running around Gotham regardless, it may as well happen while Jason is around to supervise.

** Kei is aware she could get funding by overpowering almost anyone and just taking their stuff, she decides against “punching down” and going after people who are treated as BeneathNotice by the authorities. Instead, she comes up with her MuggingTheMonster scheme below.

** Chapter 11: With encouragement from Stephanie, Kei finally explains the situation with her brother and her jinchūriki status to them, clarifies the threat represented by the League of Assassins, and helps Tim and Steph figure out some of the magical strangeness happening in Gotham.

** Everyone who meets Kei and Hayate reasonably assumes they’re metahumans, at least until Tim’s DNA analysis comes back.

* AlmostOutOfOxygen: Kei, during her first C-rank mission when she was trapped in a Water Prison Jutsu.

* AuthorityEqualsAsskicking: So true. Kei finds it amusing that the Hokage needs guards when the one who holds the title is usually the most powerful person in the village, and is probably the one who needs them the least.
* BackToBackBadasses: Kei and Obito, when they were fighting in tandem in earlier chapters. [[spoiler:They were so good at it that the Iwa-nin decided to take Kakashi (a newly minted jonin) hostage--as the easier target--in the Kannabi Bridge arc.]]

* BadassInDistress: Kakashi (in one arc), Kei (in the arc after that), and later Kushina. Obito also counts as this, during the same arc as Kushina.

** On one hand, Kei’s natural drive to protect Hayate has made her more moody and desperate the longer she’s separated from him. Seeing as Kei is a jinchūriki, her long fuse is attached to a much larger bomb than most people’s tempers.

* CultureClash: Most commonly exemplified by the interactions between Jason and Hayate in the former’s apartment.

** Every time Kei runs into the League of Assassins, one of these ensues. She refuses to kill them, despite their persistence, because leaving a trail of bodies in Gotham is an excellent way to get on society's bad side. Her issue is their tracking skills, which means she has no time to rest between attacks until she can find a way to lose them. It takes until she cuts a deal with the Bats before she can fully lose them.

** Hayate doesn't have the sensor range to be able to find Kei in such a large city without her sending up a deliberate flare, and lacks the personal history and cultural context to make fully informed decisions about how he behaves in Gotham. As a result, he tends to stay mostly in Crime Alley.

* EveryoneHasStandards: Kei is aware she could get funding by overpowering almost anyone, she decides against “punching down” and going after people who are treated as BeneathNotice by the authorities. Instead, she comes up with her MuggingTheMonster scheme below.

** Kei and Jason are both dangerous teenage fighters without a no-kill policy, and their protective instincts are focused on the same kid. Kei is a PersonOfMassDestruction, but she chooses to fight nonlethally in Gotham to keep a lower profile. Jason, meanwhile, is a BadassNormal putting together enough resources to become a crime lord to rival Black Mask and doesn’t especially care how many bodies are left in his wake. Both of them also have contrasting relationships with the League of Assassins, with Kei as a target and Jason having been trained by them.

** Hayate works around this problem through technology when meeting Robin and Spoiler, though he does accidentally fry the former's gauntlet computer with his ShockAndAwe powers.

* MoralityPet: After realizing that he can’t allow an injured metahuman to disappear into the system, Jason takes Hayate under his wing as this. He is extremely aware this choice is throwing a monkey wrench into his plans and his ability to execute them, and Hayate's actions are personally causing him a lot of stress, but refuses to go back on it.

** Kei accidentally makes both Tim and Dick think that she has it out for all other ninjas by being ominously cryptic. Fighting League assassins and occasional bursts of undirected KillingIntent don’t help her case.
** Jason runs into and hires “Genbu” (Kei in a mask) to distract the Bats and is only told afterward that she’s Hayate’s missing sister, accidentally squandering the opportunity to reunite them.

* SwitchingPOV: Aside from Kei's usual focus, other POV characters include Hayate, Jason, Dick, Tim, and Kakashi.
* TastesLikeFriendship: Jason quickly takes this tack with Hayate, reasoning that he has to feed the kid. Later on, he notes that Hayate reciprocates by making him post-patrol meals and is a little exasperated that the kid keeps ruining his sleep schedule over it.
** Kei also attempts this with Tim, but frames it as a thank-you for helping her move into a safehouse. Tim doesn’t really notice the overture.

** Kei at one point refuses to "do the {{Franchise/Pokemon}} thing," referring to DefeatMeansFriendship toward Tailed Beasts.

[[/folder]]
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!!''A Ninja's Guide to Gotham'' contains examples of:
[[folder:A Ninja's Guide to Gotham]]
* AngerBornOfWorry: The first time Jason catches Hayate following him during a job, he starts shouting at him and orders him out of the building. Hayate, unsurprisingly, is unfazed.
* BigBrotherInstinct: Centered on the same kid, even:
** On one hand, Kei’s natural drive to protect Hayate has made her more moody and desperate the longer she’s separated from him. Seeing as Kei is a jinchūriki, her long fuse is attached to a much larger bomb than most people’s tempers.
** This trope crosses with Jason’s WouldNotHurtAChild policy upon his and Hayate’s first meeting, which results in Red Hood taking an injured young ninja under his wing.
** In return, Hayate thinks they’re both overprotective. [[UsefulNotes/JapaneseSiblingTerminology But he does call them “Oneesan” and “Aniki” in response]], showing that he appreciates them.
* ChildSoldiers: Discussed and pulled apart by various characters’ stances on the topic.
** Kei (16) and Hayate (14) are both this, being a special jōnin and a chūnin respectively. Of the two of them, Hayate is much more upbeat about it because he has no other frame of reference for his life.
** Jason hates this concept down to his bones, thinking of the entire teen vigilante lifestyle as what got him killed in the first place. And on top of that, everyone he knew seemed to just carry on without learning anything from his death.
* ConditionedToAcceptHorror: Jason is stunned by what information Hayate offers about his life thus far, and is sure that the society he came from is a League of Assassins-tier abomination. Every time Hayate easily accepts Jason’s violent tactics, it makes him more and more uncomfortable.
* CultureClash: Most commonly exemplified by the interactions between Jason and Hayate in the former’s apartment.
** Tim and Hayate’s first interaction is almost entirely at cross-purposes. While Hayate is content with the changes Jason has made to Crime Alley and doesn’t mind the violent enforcement incidents (including decapitation) because he’s from a barely-not-feudal society, Tim is worried that Red Hood is inducting kids into his gang as he expands his influence.
** Kei is very aware that leaving a trail of bodies in Gotham is a bad idea, even if her commanding officers would view any deaths as self-defense given her circumstances. As a result, she spends most of her time avoiding conflict anywhere she can to remove the chance of something going wrong. Hayate is…not so careful, because he is immediately dropped into a fight and doesn’t know anything about Gotham.
** In a much less dramatic example, Kei and Tim briefly discuss preferred pronouns and the author points out in a note that Kei transmigrated before gay marriage was even legal in the US.
* CurbStompBattle:
** Jason's first appearance shows exactly how outgunned the standard Gotham goon is in a fight with the Red Hood, taking out more than twenty armed opponents within ten minutes.
** Every time Kei runs into the League of Assassins, one of these ensues. She refuses to kill them, despite their persistence, because leaving a trail of bodies in Gotham is an excellent way to get on society's bad side. Her issue is their tracking skills, which means she has no time to rest between attacks until she can find a way to lose them. It takes until she cuts a deal with the Bats before she can fully lose them.
** Hayate describes his own encounters with the League of Assassins like this as well; later, it's revealed that he attacks from under an invisibility genjutsu and [[ShockAndAwe shocks them unconscious]].
* DecapitationPresentation: Offscreen, Jason tracks down the lieutenants of the biggest drug-running operations in Gotham, kills all of them, and tosses the duffel bag full of severed heads onto the table at the next big meeting to establish dominance. Other characters mention hearing about it and wonder what kind of person would go that far.
* DramaticIrony: Every single one of the POV characters is missing some vital information that would otherwise change their decisions. Much entertainment is had from watching them stumble toward or away from the correct conclusions.
** Kei has no idea that Hayate landed in close proximity to a gang fight and was subsequently picked up by Jason. He's been living in Crime Alley since then, which is one of the areas Kei hasn't searched thoroughly because of Red Hood's presence.
** Hayate doesn't have the sensor range to be able to find Kei in such a large city without her sending up a deliberate flare, and lacks the personal history and cultural context to make fully informed decisions about how he behaves in Gotham. As a result, he tends to stay mostly in Crime Alley.
** Jason doesn't know that Kei and Hayate are related when he meets each of them, or that they're looking for each other. He also doesn't know that Hayate has been noticed by the local vigilante population under the name "Suzaku."
** Tim and Dick don't know that Kei's whole purpose to find Hayate and stay out of trouble, primarily because she refuses to tell them anything directly. They also assume that "Suzaku" is part of Red Hood's gang, as opposed to being just a kid TrappedInAnotherWorld that Jason is trying to look after on the side.
* EveryoneHasStandards: Kei is aware she could get funding by overpowering almost anyone, she decides against “punching down” and going after people who are treated as BeneathNotice by the authorities. Instead, she comes up with her MuggingTheMonster scheme below.
* FishOutOfWater: Hayate, who was raised entirely in Konoha and doesn’t know how guns, cars, or digital technology work. Luckily, he runs into Jason in the first ten minutes.
* {{Foil}}: All over the place.
** Kei and Hayate’s circumstances are constantly contrasted. While Kei landed in Gotham with some idea of how to survive in a modern city, she’s beset by circumstantial difficulties and the League of Assassins. Hayate, meanwhile, was immediately scooped up by an up-and-coming mob boss who WouldNotHurtAChild and is on vacation by comparison.
** Hayate and Tim are respectively a NinjaBrat and a TeenGenius vigilante, and they have very different moral standards despite being nearly the same age. Tim is appalled by Red Hood’s rise to power, while Hayate approves of or at least accepts his methods.
** Kei and Jason are both dangerous teenage fighters without a no-kill policy, and their protective instincts are focused on the same kid. Kei is a PersonOfMassDestruction, but she chooses to fight nonlethally in Gotham to keep a lower profile. Jason, meanwhile, is a BadassNormal putting together enough resources to become a crime lord to rival Black Mask and doesn’t especially care how many bodies are left in his wake. Both of them also have contrasting relationships with the League of Assassins, with Kei as a target and Jason having been trained by them.
* TheFourGods:
** Kei picks the mask name “Genbu” as an inside joke because she’s wearing mostly black and an ANBU mask designed to look like Isobu’s face.
** Hayate accidentally chooses the rogue identity “Suzaku” as an on-the-spot option while talking to Robin, unaware of his sister’s decision. It serves as one of many connecting elements between them.
* HydroElectroCombo: Kei and Hayate's primary nature transformations form this dynamic.
* InternalReveal:
** Chapter 6: After almost three weeks of silence on the topic, Hayate explains what a jinchūriki is to Jason.
** Chapter 10: Kei finds out that Hayate, as Suzaku, is a known associate of Red Hood.
* ItSeemedTrivial:
** While Hayate is aware that Jason has seriously conflicted feelings about the Batfamily thanks to his status as TheEmpath, he hasn’t been able to pry the reason out of him. As a result, he accidentally explains a fair bit about Red Hood’s personality and policy to Tim, after catching him attempting a preliminary investigation into Crime Alley.
** Initially, Gotham's heroes are pretty unsure of whether Genbu (Kei) and Suzaku (Hayate) are related rogues, and so they don't mention them to each other. This goes out the window when Tim runs their DNA through the Batcomputer and finds out that they're siblings.
* LanguageBarrier: Hayate only speaks Japanese with some loanwords thrown in, sharply limiting the number of characters he can easily interact with. Luckily, Jason’s a Bat-trained vigilante, and that includes foreign languages. Kei, meanwhile, is fully bilingual with a strong accent, so she doesn't have to deal with this.
** Hayate works around this problem through technology when meeting Robin and Spoiler, though he does accidentally fry the former's gauntlet computer with his ShockAndAwe powers.
* LockedOutOfTheLoop: Multiple characters are keeping secrets that can cause trouble down the line, or would have cut much of their problems short.
** Kei doesn’t trust anyone in Gotham, so she avoids giving Batman, Nightwing, or Robin much information about who she is or what her motivations are. She only seeks them out when Red Hood specifically pays her to and when she’s already worn down by being constantly pursued by Ra’s Al Ghul’s assassins. Kei also knows precisely who the mysterious Red Hood is, and has no intention of revealing that information to the Batclan (whose identities she also knows). She only has the information because she’s a transmigrator, which she can’t explain.
** Tim, after meeting both Kei and Hayate, works out quickly that they’re related. Unfortunately, he also learns that one or both of them murdered two gangsters a few weeks ago and knows the latter is basically working for the Red Hood. As a result, he avoids mentioning Hayate’s activities to Kei. Similiarly, Dick, having met Kei at her cagiest, decides against mentioning “Suzaku” to her in case it stresses her out more. Not long afterward, Tim’s investigation reveals that Red Hood’s smallest lackey is her brother.
*** Kei finds out that the Bats knew about her brother in chapter 10, and narrowly retains control of her temper as one of her most important buttons is accidentally pressed.
** Jason tries to hide his criminal dealings from Hayate, but quickly discovers that Hayate is both aware of how gangs work and can escape Jason’s security measures whenever he feels like it, which lets him roam Gotham at will. That said, he doesn’t know Jason’s real name, despite living in his apartment for the better part of a month.
* McNinja: Kei spitefully calls the League of Assassins this by name, frustrated with their constant pursuit.
* MissedHimByThatMuch: Kei and Hayate's arrival in Gotham separated them. Much of the story from that point onward is both of them repeatedly running into people who know about the other sibling, but not being able to get information or connect enough dots to reunite.
* MobWar: Ongoing between Black Mask and Red Hood. Kei and Hayate both end up on the wrong end of gang-related shootouts on as early as their first night in Gotham, though only Hayate is injured.
* MoralityPet: After realizing that he can’t allow an injured metahuman to disappear into the system, Jason takes Hayate under his wing as this. He is extremely aware this choice is throwing a monkey wrench into his plans and his ability to execute them, and Hayate's actions are personally causing him a lot of stress, but refuses to go back on it.
* MuggingTheMonster: Invoked and exploited. Kei acquires funds by using Transformation Jutsu to disguise herself as an easy target in some of the worst neighborhoods in Gotham, then overpowers the would-be muggers and takes their cash. But, because of TechnologyMarchesOn, she’s unable to make use of any cards she finds, which is where the majority of most people’s money really is.
* OneManArmy: Hayate notes that one of Jason’s tactics for rooting out rival criminal enterprises is “kick down the front door and shoot them all to death,” and his very first fight has him winning a twenty-on-one shootout without taking a hit on anything but his armor.
** Kei is also this, but no one wants her to reach the point where she has to demonstrate it.
* PersonOfMassDestruction: Kei, which is even more dangerous in a city with as many people as Gotham. Unfortunately, Kei refuses to mention this to the Bats and the only person Hayate tells about this is Jason, who has MobWar to manage and a ResurrectionRevenge plot to carry out.
* PoorCommunicationKills: Almost every character is keeping secrets from the others. Usually on purpose, but sometimes they just don’t communicate well.
** Kei accidentally makes both Tim and Dick think that she has it out for all other ninjas by being ominously cryptic. Fighting League assassins and occasional bursts of undirected KillingIntent don’t help her case.
** Jason runs into and hires “Genbu” (Kei in a mask) to distract the Bats and is only told afterward that she’s Hayate’s missing sister, accidentally squandering the opportunity to reunite them.
* RageBreakingPoint: After a certain point, Kei suspects the whole goal of the League of Assassins' harrassment campaign is to [[InvokedTrope push her until she snaps and kills someone]], preferably in front of the Bats.
* RecklessSidekick: Jason perceives Hayate as an aspiring example, and it scares the hell out of him. He repeatedly remarks in his narration that he doesn't think Hayate has an ounce of sense and that he'll get hurt or killed at ''some'' point with all the sneaking around. In fact, this is a SubvertedTrope because Hayate is a competent shinobi in his own right. His POV chapters reveal that he takes numerous precautions to avoid detection or conflict even within Red Hood's territory, and doesn't fight street crime like a vigilante would. He even gives up a chance to potentially reunite with his sister when he suspects the opportunity ''could'' turn into a trap he can't escape.
* SecretIdentity: Several, since Gotham’s one of the most famous superhero story settings of all time. Besides the Batfamily, Kei chooses the vigilante moniker “Genbu” and Hayate (entirely coincidentally) chooses “Suzaku.”
* SecretSecretKeeper: Kei already knows the Batfamily’s identities due to being a transmigrator, but isn’t interested in sharing the information.
* SlaveryIsASpecialKindOfEvil: Hayate explains to Jason that he has absolutely no problem with human traffickers being killed, because Konoha’s policy is to execute them on the spot. Jason, who was trying to explain [[SuperhumanTrafficking why]] he didn’t want Hayate following him at night, is mostly disturbed by his total nonchalance.
* SpottingTheThread: There are a number of details that connect Kei and Hayate’s SecretIdentities, mostly because they don’t work very hard to hide them. Hayate doesn’t even know that masked identities are a thing until Jason explains.
** Jason notes that “Spike” wears the same kind of kunai holster that Hayate does, and asks about it. Hayate immediately identifies the other ninja as Kei once Jason starts elaborating on their encounter.
** Tim also notices that “Genbu” and “Suzaku” share equipment loadouts, down to the katana each of them wear on their hips. Which is a problem, because kunai also leave distinct wounds and indicates one of them killed two people.
* SwitchingPOV: Aside from Kei's usual focus, other POV characters include Hayate, Jason, Dick, Tim, and Kakashi.
* TastesLikeFriendship: Jason quickly takes this tack with Hayate, reasoning that he has to feed the kid. Later on, he notes that Hayate reciprocates by making him post-patrol meals and is a little exasperated that the kid keeps ruining his sleep schedule over it.
** Kei also attempts this with Tim, but frames it as a thank-you for helping her move into a safehouse. Tim doesn’t really notice the overture.
* TrappedInAnotherWorld: What this story is from Kei and Hayate’s perspective. Given that both Gotham and Konoha are extremely weird from the other’s perspective, it’s a fair enough read.
* WeirdnessSearchAndRescue: Since Kei and Hayate are important to many people in Konoha’s upper administration, the village’s interlude shows them working out how to be this.
* WhiteMaskOfDoom: Kei’s vigilante guise consists of one of these worn over her face, which she admits is just an art project everyone is now taking too seriously. She still considers it more effective a disguise than the classic Robin DominoMask.
* WouldNotHurtAChild: Jason’s ironclad policy within his territory, which is the main difference between his gang’s behavior before and after his takeover. He’s furious at the idea of ChildSoldiers and absolutely refuses to let Hayate follow him around as a sidekick. It’s also what gets him stuck looking after Hayate in the first place, because he’s unwilling to put Hayate into the hands of any of the corrupt authorities in the city.
* WretchedHive: Kei's opinion of Gotham, due primarily to frustration. The city’s aura of despair and gloom interferes with her SupernaturalSensitivity and gives her sensory overload headaches that require either Isobu’s chakra or a lot of painkillers to counteract. Most of the money she acquires is from mugging people who clearly planned to rob her first, and the social services and police in the city are untrustworthy from her perspective. Also, every single time she’s gone out, someone’s been shooting up the place.
** If there’s one place in Gotham that exemplifies this, it’s Crime Alley/Park Row, the crime-riddled neighborhood where the Waynes were gunned down decades ago. Under Jason’s new management, Hayate notes that it’s actually improving.
* WrongAssumption:
** Due to Kei’s costume choices, they assume she’s a new vigilante or a new rogue in town. In truth, Kei is TrappedInAnotherWorld and looking for her missing brother, but doesn’t trust any of the other characters enough to ask for help. The costume was a whim and now she’s too far into the game to turn back.
** Jason, who is familiar with the League of Assassins, figures that Hayate is a product of another secret murder-conspiracy cult he just hasn’t heard of. He’s wrong, but it’s reasonable based on what he knows.
** Everyone who meets Kei and Hayate reasonably assumes they’re metahumans, at least until Tim’s DNA analysis comes back.

** Chapter 11: Kei finds out that Hayate, as Suzaku, is a known associate of Red Hood.

*** Kei finds out that the Bats knew about her brother in chapter 10, and narrowly retains control of her temper as her RelativeButton is accidentally pressed.

* InternalReveal: After almost three weeks of silence on the topic, Hayate explains what a jinchūriki is to Jason in chapter 6.

** Tim, after meeting both Kei and Hayate, works out quickly that they’re related. Unfortunately, he also learns that one or both of them murdered two gangsters a few weeks ago and knows the latter is basically working for the Red Hood. As a result, he avoids mentioning Hayate’s activities to Kei.
** Dick, having met Kei at her cagiest, decides against mentioning “Suzaku” to her in case it stresses her out more. Not long afterward, Tim’s investigation reveals that Red Hood’s smallest lackey is her brother.

* LanguageBarrier: Hayate only speaks Japanese with some loanwords thrown in, sharply limiting the number of characters he can easily interact with. Luckily, Jason’s a Bat-trained vigilante, and that includes foreign languages.

* MoralityPet: After realizing that he can’t allow an injured metahuman to disappear into the system, Jason takes Hayate under his wing as this.

* PersonOfMassDestruction: Kei, which is even more dangerous in a city with as many people as Gotham.

* CasualDangerDialog: Team Minato seems to have the makings of this. Minato is the king of it.

** Tim and Dick don't know that Kei's whole purpose to find Hayate and stay out of trouble, primarily because she refuses to tell them anything directly. They also assume that "Suzaku" is part of Red Hood's gang, as opposed to being just a kid TRappedInAnotherWorld that Jason is trying to look after on the side.