Fanfic / Mischief In Musutafu and Other Such Tales

Mischief In Musutafu and Other Such Tales is an Alternate Universe My Hero Academia fanfiction series by InsomNyaC on Archive of Our Own.

The story starts when Midoriya Izuku, after his initial encounter with All Might when he is told he cannot be a hero, he simply...stands on the rooftop for a few hours aimlessly, and then goes home, in despair that his idol crushed his dreams. It's not until the next day that he finds out that his childhood friend/bully Bakugou Katsuki is at the hospital after a villain attack...or that All Might also crushed Izuku's ribs along with his dreams.

Cue an investigation on Heroic neglect against All Might that reveals confusing family connections, too many people needing families, and changes the status quo forever.

The series has the following entries:

1. Mischief in Musutafu: first fic, taking place during the ten months prior to the UA entrance exam. Complete
2. Mischief in Motion: the sequel, starting from the UA entrance exam.
3. A Collection of Mischief: series of one-shots set in the same universe

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This series provides examples of:

• Adaptation Relationship Overhaul:
  • Monoma is in class 1-A instead of 1-B so his antagonistic attitude is shifted towards them and is very much downplayed.
  • Izuku is on good terms with many of the canon antagonists because of him being All For One's son.
  • Izuku also meets Hitoshi, Tenya, Shouto, and Kirishima far earlier than canon, so they all become good friends prior to going to UA.
• Adaptational Badass:
  • Slightly overlapping with Adaptational Superpower Change; Katsuki's Explosion Quirk, instead of making him sweat a substance that's "explosive like nitroglycerin", straight up is nitroglycerin. This makes Katsuki a Poisonous Person, on top of his canon abilities. Unlike most instances of this trope, this is not portrayed as a good thing, and Katsuki never deliberately uses this property of his quirk.
  • Kirishima Eijirou inherits One For All.
  • Hitoshi learns how to use guns from Snipe in the months prior to the UA entrance exam so he can pass the physical.
  • Monoma Neito's quirk was originally just copying a limited amount of quirks for a limited amount of time. Here, his quirk is a combination of All For One and a beefed-up version of Copy that lets him pass around those copies to other people.
• Adaptational Intelligence: Izuku certainly isn't stupid in canon, but here he aces the written portion of the UA entrance exam two months into his last year of middle school. It's also strongly implied that Katsuki could have done the same.
• Adaptational Jerkass: All Might, big time. He is incredibly quirkist, completely dismissing Izuku's desire to become a hero because he doesn't have a quirk, even though his former sidekick Sir Nighteye is effectively quirkless 23 hours per day, rarely uses it, and it doesn't aid him in battle anyway. It takes All Might a long time and several What the Hell, Hero? speeches from multiple sources to start realizing that what he did was wrong.
• Adaptational Nice Guy:
  • Death Arms was the guy who said he couldn't save Katsuki due to a bad quirk matchup in canon. In this fic, not only he kept trying but was eventually able to succeed after tapping in hysterical strength.
  • All For One, aka Midoriya Hisashi, is most certainly not the kind of person who wants to take over the world For the Evulz and stole other people's quirks on "almost" a whim as he did in the manga. Here, he is the epitome of a family guy, wants to destroy hero society because he believes the current system to be unstable, and most of his "stolen quirks" were either given to him at the Dawn of Quirks era (when people didn't want them) or taken from the dying. That said, he acknowledges that he's a villain and has no regrets about them, and everyone knows that he's The Sociopath bordering on Blue-and-Orange Morality.
  • The League of Villains as a whole. Their goal to destroy the Symbol Of Peace and the current Hero Society is the same, but instead of doing so via killing people, their crimes mostly extend to vandalism and they want to expose the instability of the system. The name "League of Villains" is mostly ironic because they're only villains according to the law, and prior to the Shie Hassaikai battle, they were mostly dismissed as pranksters by the heroes. They also turn down certain members like Muscular from joining.
  • Mineta Minoru is still a pervert but he consciously tones it down after a bit of a talking to from Izuku, and is a lot more respectful towards his classmates. Also, unlike canon where he wants to be a hero because he believes heroes to be Chick Magnets, here he doesn't want to be in the hero course but in Management, and was forced into the Hero course by his parents. As a result, he has a much better relationship with the class 1-A students.
• Adaptational Superpower Change: Izuku doesn't get One For All; instead he has some kind of passive precognitive quirk that went unnoticed for most of his life because its most tangible effect prior to Izuku being aware of it was that it just constantly led him to fights. Later it's revealed that Izuku was originally Quirkless, but his father All For One gave him Danger Sense, which later mutated into its current form.
• Affectionate Nickname: Hisashi calls Eri his "little dragon princess".
• All for Nothing: Endeavor punches a wall in rage after the reveal of All Might's injury because he was supposed to surpass All Might to get the Number 1 spot, not take it by default as the man withers from his injuries.
• Amnesiac Dissonance: Kurogiri admits that by the time he had regained his memories as Shirakumo Oboro, he had already developed a very different personality and identity, complete with different hobbies and speech patterns. so he can't really identify with "Shirakumo Oboro" anymore.
• Blazing Inferno Hellfire Sauce: The Bakugou family keeps ghost peppers in the kitchen. For eating.
• Born Lucky: The most obvious effect of Izuku's quirk is to make him ridiculously good at anything luck-related. Izuku first demonstrates it by winning several matches of Rock-Paper-Scissors in a row against Katsuki. He also has Improbable Aiming Skills and is fantastic at poker because of this.
• Broken Pedestal:
  • All Might falls in the eyes of just about everyone who knows him after he displays his quirkist views in his talk with Izuku and crushes his spirit. This incident also reveals that he generally doesn't properly follow protocol and is responsible for many cases of heroic neglect.
  • Played for Laughs when Izuku and Katsuki find out that Inko knows how to curse.
• Bungled Suicide: The reason Izuku decides not to commit suicide is because the buildings in his area are too short for him to be sure he would die upon impact.
• Celeb Crush: Mirai once had a boy crush on All Might.
• Cult of Personality: Played for Laughs. Since Nedzu goes by the moniker "Rat God" in the group chat, the other Recommendation Students group chat led by Izuku calls itself "the Church of Nedzu" and uses nicknames that make them all sound like cultists.
• Dartboard of Hate: Kurogiri has a few set up in his bar, with All Might and Endeavor's pictures stuck on them. Tomura and Dabi have knife-throwing competitions on them.
• Death of Personality: Discussed. Due to Hisashi and Naomasa's mental link, and Hisashi being much older and more powerful than Naomasa, the detective suffered a real risk of his personality being erased by Hisashi, essentially making Hisashi a man with two bodies. By the time Hitoshi manages to separate them, some parts of Naomasa's mind have already been irrevocably changed.
• Detrimental Determination: All Might's insistence to keep being a hero and save as many people as possible is physically destroying him and ending his career faster.
• Disabled in the Adaptation:
  • Izuku has been diagnosed with ADHD.
  • Katsuki has been formally diagnosed with OCD and anxiety.
  • Tenya also has OCD.
• Entertainingly Wrong: The One For All Vestiges and half the internet is convinced that Izuku's mom is Sir Nighteye.
• Feel No Pain: Izuku has an absurdly high pain tolerance threshold to the point that he did not even notice his broken ribs until the next day when he bent the wrong way and passed out. This also means that he could not feel Danger Sense in its original form because its warning system manifests through headaches - obviously Izuku can't feel them.
• Fights Like a Normal: Sir Nighteye, which is lampshaded repeatedly when he's talking about All Might's Fantastic Ableism, as he should know better than anyone that Sir Nighteye is no more physically capable than a quirkless person. Ditto for Eraserhead.
• Finishing Each Other's Sentences: Hisashi and Naomasa after Hitoshi manages to sever their mental link.
• Government Conspiracy: The corruption of the Hero Public Safety Commission seems to be an open secret among certain circles.
  • When All Might confides in Endeavor (No. 2), Hawks (No. 3), and Best Jeanist (No. 4) about his Career-Ending Injury and impending retirement, Best Jeanist thinks to himself that it's extremely likely Hawks will be the next No. 1 in case the Commission decides to "remove" Endeavor.
  • Hisashi decides to illegally adopt Eri and fake her Quirk registry because he doesn't want the Commission finding out about her.
  • Hawks doesn't remember his own birth name and Dabi had to dig up some illegal documents for it.
• Hypocrite: All Might is called this by many people for telling Izuku he can't be a hero without a Quirk. That's because he was Quirkless himself, he knows and has worked with heroes who have non-physical quirks, and is known as the guy whose catchphrase is that "anyone can become a hero".
• I Am Not Pretty: Rare male example with Shouto. When Hitoshi points out that Izuku's family keeps "adopting all the cute boys", it's revealed that Shouto doesn't think he's good-looking because of his facial scar. Izuku points out to him that he's the most conventionally attractive of all the guys in their group even with the scar, and if someone doesn't look past it then they're not worthy of Shouto's attention.
• Internal Reveal:
  • During Hero Con, after All Might is seen arguing with Sir Nighteye over his impending retirement, he chooses to reveal to Endeavor, Hawks, and Best Jeanist that he has no choice but to retire soon because of his gut injury. He also shows them his powered-down form.
  • FatGum, Mirio, Tamaki, and some other pro heroes start figuring out that Endeavor is abusive when they see Shouto openly refer to Hisashi as "better dad" and that he willingly left home instead of being kidnapped.
• It's Not You, It's My Enemies:
  • Inko never told Izuku that his two uncles are pro-heroes because she knew that Izuku and Katsuki would boast about this to everyone, and their families did not want them targeted for this connection.
  • This is Sir Nighteye's stated reason for not dating, but later he figures out that he wouldn't have dated a civilian anyway.
• Jerkass Realization: Katsuki's Near-Death Experience at the hands of the Slime Villain and the news that nobody saw Izuku after Katsuki told him to jump off a roof makes him seriously reevaluate his past behaviour. He finds out pretty quickly that Izuku is fine and went home but this change of heart sticks and he resolves to be supportive to him and everyone who is looked down upon, effective immediately.
• Locked Out of the Loop: There are several loops regarding the Midoriya family situation. First there are the people who are full family members (plus the adopted ones and the Bakugous) who are told the full truth, then there are the close family friends who are told some edited version of some true facts (like Izuku's quirk status or their involvement with villainy), and finally there's everyone else. Lampshaded in Izuku's birthday party, when Dabi notes that nobody in attendance seems to be on the same page.
• Mayfly–December Romance: Hisashi is over 200 years old by the time the fic starts, while Inko is in her thirties. This trope is the stated reason why Hisashi never dated anyone seriously prior to Inko, and the subject gets brought up a lot by outsiders.
• Me's a Crowd: A standard tactic by the League. Everyone goes around disguised as Mr. Compress - Himiko using her quirk and Dabi in a proper disguise - so that their enemies do not have a description of them and don't know who to target.
• My God, What Have I Done?: Played for Laughs. Sir Nighteye seriously regrets introducing All For One to Principal Nezu.
• No Social Skills: Deconstructed with Hisashi. He is The Sociopath, so he doesn't understand a lot of social norms, and that has in large part contributed to the reasons he is a villain. A big example is when he gives his quirkless daughter a quirk within seconds of meeting her for the first time, while she was a grown woman who grew up without her. From his point of view, he was just helping his family, but from her point of view this complete stranger who walked out on them forced a major medical decision on her within seconds of meeting her without asking for her consent or asking if she wants a quirk in the first place - which she doesn't. It's only when she puts it in these terms that Hisashi starts realizing why his brother took issue with him.
  Nighteye: My brother-in-law has no understanding of social norms.
  • These issues also spread to the rest of his family, particularly the younger ones. For example, his reaction to Izuku deciding to become a vigilante is to support him, and Katsuki uses Hisashi's connections to gift Hitoshi a gun so he can pass the practical exam in a country where possessing firearms is extremely illegal. Only Hitoshi thinks that this gift is unreasonable. They also all get Hisashi's habit of sharing Too Much Information with complete strangers, which often makes them uncomfortable.
• Not-So-Harmless Villain: The League of Villains. At first they are treated as a nuisance by the Heroes because their crimes were mostly illegal quirk usage and minor vandalism. Then the Shie Hassaikai raid happened, which confirmed the League's connection with All For One, and showed that the League is terrifyingly powerful quirk users capable of killing if needed.
• One Degree of Separation:
  • Izuku is left heartbroken by All Might, and then he finds out that his Uncle Mirai was All Might's sidekick Sir Nighteye.
  • There is also Aizawa Shouta being Izuku's other uncle, so the family has a direct connection to Yuuei and Principal Nezu.
  • Katsuki's parents and Best Jeanist know each other personally due to their jobs in the fashion industry, and they have even collaborated a few times.
  • Due to Izuku's father being All For One, the family has connections with most of the Underground (or at least, the important players).
• O.O.C. Is Serious Business:
  • When Izuku doesn't get excited to talk about All Might, everyone immediately realizes that something's incredibly wrong. Inko immediately offers comfort while Katsuki asks whose ass he needs to kick without even asking for details.
    Katsuki: The only reason I believed the Nerd was I knew he would never make up some shit like that. Hearing him go from praising the ground All Might walks on to talking about him like this basically overnight is just weird.
  • According to the author notes, Izuku was extremely confused by Katsuki acting nice to him after the villain attack.
• Paper-Thin Disguise: When he's away from home Shouto wears an eye patch and a white wig. He gets recognized instantly, but he's more concerned about not drawing attention from random people on the street; he just explains himself to anyone who's actually looking for him.
• Point of Divergence: In this fic, instead of leaving the rooftop and running across the Slime Villain attacking Katsuki, Izuku dissociates on the rooftop for several hours and finds out about the attack after he goes home. As a result, Katsuki suffers from a Near-Death Experience and ends up hospitalized, which triggers his Jerkass Realization and causes a complete change in attitude. It also causes a number of other changes, such as All Might losing his good rapport with several heroes, and Izuku becoming homeschooled. While there are many other background elements that are different from canon, if not for Izuku staying on the rooftop for a few extra hours, then those elements would likely not have been discovered.
• Poisonous Person: Katsuki is one because of his nitroglycerin sweat, and the fic goes a long way to explain how a person like that would function in society. At first nobody knew that Katsuki's sweat was poisonous until Izuku licked his hand when they were little kids and was sent to the hospital as a result. Katsuki's quirk is therefore categorized as a "biohazardous" quirk, and he has a medical quirk usage license which obliges him to use his quirk in public so he doesn't accidentally poison bystanders. He also warns Monoma Neito in the entrance exam to burn off all the sweat before his quirk-copy runs out because he'll get poisoned himself from the residual sweat. The event with Izuku being poisoned also traumatized Katsuki to the point that he doesn't let anyone touch him, so as a result, he Desperately Craves Affection.
• Poor Communication Kills:
  • How the One For All versus All For One blood feud started in the first place. Hisashi has no idea why Yoichi was opposed to his ideals, so when he found out that he died and that the Second user had One For All, he assumed that Second killed Yoichi and stole his quirk. He also points out that all the other One For All users attacked him first, and he views Nana's battle against him as assisted suicide. He understands why All Might has an issue with him though. The vestiges are shocked when they hear Hisashi's side of the story, because in their minds he is a murderous monster who never cared about anyone, so they had no idea that familiar love was the reason why All For One killed Second.
  • After Endeavor finds out about All Might's impending retirement due to his Career-Ending Injury, he spends a week in an exceptionally foul mood so Shouto decides to leave the house until Endeavor calms down. Thing is, he didn't tell his siblings where he was going, and instead left a note behind that vaguely said that he'd be at a friend's house for a while, and left his phone card behind. Endeavor understandably thinks he was kidnapped and announces a search. Shouto kind of regrets what he did after a while because his lack of a proper explanation overcomplicated things.
• Power Misidentification:
  • Hitoshi's quirk is listed as Brainwashing, but everyone points out that it's actually Hypnosis.
  • In his legal papers, Hisashi's quirk is described as Dragon's Breath, which gives him fire breathing and makes him The Ageless. In reality, he is All For One, and those are two of the many quirks he has collected. The reason they actually included Hisashi being The Ageless in his official papers is to explain why has so many children popping up out of nowhere.
  • Izuku's quirk is a passive precognition quirk that mutated from Danger Sense after Hisashi passed it to him. Izuku either claims that he's quirkless, or he claims that he has a luck quirk, which is the most noticeable effect of his quirk. He's quirkless in the legal papers because there's no exam - medical or otherwise - that can prove Izuku has a quirk.
  • Eri's legal papers claim that she has a healing quirk as opposed to a Time Master one.
  • Neito uses his powered-up quirk and cooperation from class 1-A to prank class 1-B that he has a body swapping quirk.
• Precision F-Strike: When Katsuki tells Izuku that none of the heroes (other than Death Arms) tried to save him from the Sludge Villain because of "bad quirk matchup", Izuku's reaction is "That's fucking bullshit!"
• Related in the Adaptation:
  • Inko, Sasaki Mirai, and Aizawa Shouta are biological full-blooded siblings. Shouta changed his surname so his connections couldn't be traced back to his family.
  • All For One is Midoriya Hisashi, Izuku's father. He is also Monoma Neito's grandfather from his mother's side.
  • Discussed with Katsuki and the Second User of One For All, who are Identical Strangers. Second is pretty sure that Katsuki is one of his brother's descendants, but he has no way of proving it.
  • On top of all that there are a lot of adoptions. Like, an absurd amount of adoptions. Shigaraki Tomura, Toga Himiko, Dabi, and Eri are all adopted by All For One and Inko mostly through illegal means, and Shinsou is adopted by Aizawa.
• Relative Error: Endeavor, not knowing that Dabi is Touya, thinks that he and Fuyumi are boyfriend and girlfriend. When he tells them this, Shouto melts with laughter, while a disgusted Fuyumi explains that they're both gay and that she's dating the best friend of Dabi's boyfriend.
• Relatively Flimsy Excuse: Everyone pretends that Tomura, Dabi and Eri are Hisashi's biological children.
• Secret Secret-Keeper:
  • Inko did figure out that Hisashi is a villain and that he's faking what his quirk is pretty quickly into their relationship. However, he's so obviously smitten with her that she never said a word and married him anyway.
  • Spinner has figured out that Dabi is a Todoroki, but is advised by Mr. Compress not to talk about this to anyone.
  • Mirio figures out that Midoriya Izuku and Loki are the same person and that he is All For One's son, but chooses not to tell anyone.
• Shared Family Quirks:
  • Everyone in the Midoriya family tends to share Too Much Information when explaining anything.
  • They also all have a disregard for the law as long as it doesn't hurt anyone who doesn't deserve it.
  • And they also all have the tendency to adopt everyone into their family. Hitoshi complains about running out of cute boys to date because they all get instantly adopted.
  • Invoked by Dabi, who starts puffing out flames to sell the illusion that he's related to Hisashi.
• Shout-Out:
  • Izuku bases his vigilante persona on Loki from The Avengers (2012).
  • After Izuku realizes that his teachers at Aldera never read his assignments, he starts passing passages of The Hitchhiker's Guide to the Galaxy Trilogy as assignments in his English class.
  • Hisashi changes Naomasa's group chat name to Veritaserum after the Truth Serum in Harry Potter.
• Sins of Our Fathers: Discussed. Third is surprised that All For One lets one of Second's relatives hang out with his son, considering how much All For One hated Second.
• Spared by the Adaptation: Sir Nighteye doesn't die in the Shie Hassaikai raid.
• Strong Family Resemblance:
  • Izuku with his hair straightened looks near identical to his uncle Mirai. Normally he looks exactly like his mom.
  • Neito looks like a younger All For One with colour splashed on him. He also mentions that his colouration comes from his father's side of the family.
  • This trope is invoked when the Midoriyas are trying to sell the lie that Tomura, Dabi, and Eri are related to them. All three have white hair and eye colours that are normally attributed to albinism, so they blame Hisashi's albinism for that.
  • This trope is why the Second One For All user is convinced that Katsuki is related to him.
• Superpowerful Genetics: Par of the course with My Hero Academia, but there are a few notable instances.
  • Hisashi's biological children notably do not inherit quirks precisely because Hisashi is their father. As a first-generation quirk user, his quirk factor is unstable.
  • Katsuki starts suspecting that Neito may be related to Hisashi when he's given an exact description of how his Copy quirk works, as it is too similar to All For One. He then specifically asks for the quirk status of Neito's parents, and sure enough, his mom is quirkless.
• Swiss-Army Superpower: Izuku's unnamed quirk - a mutated form of Danger Sense - is a passive precognitive quirk that manifests as a "gut feeling" that guides Izuku to take appropriate actions for his situation. This has the effect of making Izuku a Weirdness Magnet, makes him incredibly lucky, gives him Improbable Aiming Skills, allows him to track down people, and makes him an Instant Expert on an ever-increasing list of subjects.
• Tangled Family Tree: An interesting case in that the lies the Midoriya family tells to cover up their complicated family situation end up being more complicated than the truth.
  • First of all, when Inko, Mirai, and Shouta were kicked out of their house by their parents, the sheer age gap between Inko and Shouta made Inko her brother's legal guardian. So when she married Hisashi, he legally became both Shouta's brother-in-law and his father (not helped by Shouta actually calling him father when he was young). The sheer confusion over this becomes a Running Gag in the series. It's also pointed out that Mirai would be in the same situation if he was any younger.
  • Hisashi and Inko are married and their only child is Izuku. The Mayfly–December Romance aspect of the relationship ironically makes it easier to explain away why Hisashi has so many children of varying ages but no serious relationships prior to Inko.
  • The Bakugou family are all honorary family to the Midoriyas, so Izuku and Katsuki refer to each other as "cousins" to other people, and this soon extends to the rest of the family as well. They rarely reveal that they're not biologically related, as most people don't pick it up with how the two interact. This is made more complicated when the Second One For All user starts speculating that the Bakugou family are descended from his brother.
  • Himiko is legally adopted by the Midoriyas due to her biological parents being abusive.
  • Shigaraki Tomura was taken in by Hisashi when his family died after his quirk accident like in canon. They lie that Tomura's biological father was actually his stepfather, that Tomura has no connection to the Shimura family, and that he was raised alongside Izuku (untrue).
  • Dabi is illegally adopted (more like claimed) by the Midoriya family when he needs a secret identity. They lie that he was the result of an old One-Night-Stand Pregnancy and that his biological mother tried to pass him off as her husband's without telling anyone. Ironically, while this story is Blatant Lies considering how Dabi is the supposedly dead Todoroki Touya, it is actually true in regards to Neito's mom. This also makes his biological siblings and mother honorary family for the Midoriyas (they keep his biodad out of it), and Shouto openly refers to Hisashi as "better dad".
  • They pass Eri as Izuku's much younger full-blooded sister. In reality, they took her in because she has no biological family left that's able to take care of her, and they really want to keep the Hero Commission away from her.
  • Hisashi is also revealed to have fathered Monoma Neito's mother as a result of a One-Night-Stand Pregnancy, making the poor guy Izuku's nephew. Oh, and said daughter is older than Hisashi's wife.
  • Shouta is in a relationship with Yamada Hizashi and has adopted Shinsou.
  • Detective Takauichi enters a polyamorous relationship with Hisashi and Inko, to everyone else's bafflement.
  • Kurogiri is also an Honorary Uncle to the family.
• Theme Naming: An accidental and Lampshaded example occurs with the names of Hisashi's illegally adopted children. Tomura means "decay", Dabi "cremation", and Eri "destruction". It also ties in with the "Deku" Alternate Character Reading of Izuku's name, though that one isn't brought up.
• There Are No Therapists: Double Subverted. Inko is a therapist, but she cannot officially help any member of the cast because she is family/friends with them, and thus biased. She is also a professional so she doesn't do unofficial sessions either.
• Weirdness Magnet: Izuku gets in so much trouble and danger that Katsuki is halfway convinced that this is his actual quirk. It turns out that finding danger is one of the effects of Izuku's quirk (he actively seeks out villain fights, and his quirk physically guides him to the location).
• Vigilante Man: Izuku and Katsuki come up with a plan to have Izuku moonlight as a quirkless vigilante so they can have him enter UA via the Vigilante Reformation Program. That's because people who enter this program don't have to take the standard exam, which is strongly biased towards physical quirks.
• You Have Outlived Your Usefulness: There were two reasons Hisashi kept Dr. Ujiko alive: he needed his medical expertice to stay alive himself, and the man was too crazy to leave unchecked. Enter Eri who heals all of Hisashi's injuries, and Hisashi's first order of business after making sure she's safe is to kill Ujiko.

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