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The twins' inked in hero academia!

Chapter Text

Everyone always wonders how and when we decided to become heroes. You too? Well, guess I could tell you, it’s not a special story though. I myself never talked much when I was younger, my sister did most of the talking, even though I was, and still am the better story teller. She always went on tangents. Ah? You also want to know about those incidents and our school lives? I hope you do know that will severely lengthen the story? You don’t mind?! Oh well, might as well have some fun with this. Lord knows hero work is stressful.


Well… where do I begin? The conversations I had with my sister might be a good point to start off… So, it began when we were but four years old.


“mu-muuu! Why are you being so slooow! Mama is gonna be mad if we’re home too late y’know!” a young girl with blond twin-tails wearing a kindergarten uniform adresses to what looks like an amorphous blob of ink, who’s wearing the same uniform as the girl. The ink blob seems to try to catch up, sliding along the ground, but not leaving a trail. The blob gurgles.


“mu-muuuuu worrdds!!!” The twin-tailed girl replies.


The blob stills and then their head shifts, a slit appears, mimicking a mouth. A childish, yet feminine voice spills out: “mumu is sorry for mumu being tired!” after this simple sentence, the mouth melts shut again.


The two girls start moving again, following their guide. “big bro hold uuuup!” the girl with twin-tails exclaims.


The elder turns around tired “mukeiko, do I need to carry you? It might be faster” he adresses the smaller blob of ink. She looks like she nods.


“big bro, big bro! Me too, me too!” The other girl immediately exclaims, to which the older boy replies with: “Nico, you know I can’t carry both you and your twin… I’m not that strong…”

“but big bro is so strong though! He could be a hero! Are you gonna be a hero?” the girl, apparently named Nico, blurts out.


In reply her brother smiles and says “I’m gonna try!” he points at his hair and continues “Even though my ‘ink hair’ isn’t that powerful of a quirk, I’m gonna try to get into UA in three years! Though,” he giggles “you two have quirks that are way more powerful than mine!”


A little later, the three siblings arrive at a small house in a cozy neighborhood, the house plate bearing the name Sumitsubo. Before they enter the house, the brother turns to the twin girls, patting their heads. “y’know, you two can do anything you will put your minds to. I just know it.” he notes “I just know it.” after this, he turns to the door going inside. A feminine voice welcomes them home.



The sun is setting, and three figures are seen walking alongside the road. The twins from last time are there, alongside an older man. They are older than they were in the previous scene, looking like they’re around seven years old. The ink-like twin now has arms and a more distinguishable head, while her sisters hair is freed from the twin-tails and looks like it was dipped in ink. They’re both wearing casual clothes and are carrying backpacks.


“Ne, papa! Why is big bro not taking us home today~?” Nico sing-songs.


“have you forgotten?” the older man, apparently the two girls’ father ask, bemused “he’s on the way to the UA exam, sweetheart! Oh, I am so proud of my boy!”

the more human looking twin runs in front of her father, and then begins running backwards to look him in the eyes, while less human looking one slides along the ground faster trying to catch up. Her face shifts and a proper mouth appears, muttering.


“Nico… how’d you forget that?”


The addressed twin looks at Mukeiko sheepishly


“hehe… no idea!”








both the father and the Mukeiko face-palm at this.


“annyyyywayssss… how do you guys think big bro’s doing~?” Nico awkwardly says



“I’m sure he’s doing great sweetheart! Hey, you two did say that you wanted to do the same as him right?” the father muses amusedly “Have you two thought up hero names?”


“yeah!” both of the twins say, before Mukeiko adds: “Big bro helped us..!”


“Oh? What are they then?”


“I’m scribble!” Nico cheers


“And I’m Inky…!” Mukeiko squeaks


“ahaha! Good! Well, we’re here!” the father opens the door as he says this “Let’s greet your mom! I’m sure she’ll be happy… you’re... home...? S-sweetie?! w-what’s wrong?!” he suddenly exclaims


In the living room sits a weeping slime woman. When she processes the question she replies unsteady


“k-kami… Kamisumi…” she sobs “He… he!” she’s not able to finish her sentence before breaking down. She is able to point to the tv.


On the screen a paused news program is displayed, on which the brother’s picture is displayed. Below the picture there is one message


“young male high school student dead in villain attack, having protected three children”



It’s dark, nearly night. The stars aren’t visible due to dark clouds, it seems like it’s going to rain soon. The Sumitsubo sisters, who are now seen wearing middle school sailor uniforms, are running home in a hurry. The ink-like twin now looks distinctly humanoid, bearing both legs and arms, detailed eyes, and what looks like twin-tails. The other twin now has a singular ponytail, located high on her head.


“c’mon mu-mu! It’s gonna rain soon! We don’t want you to dilute!~“ Nico sing-songs in a teasing voice


“you KNOW that doesn’t happen anymore….” the annoyed reply resounds. Mukeiko narrows her eyes, but then her gaze turns soft again. “But let’s hurry anyways. I don’t want you to get a cold”


“yeah, yeah.” Nico answers back. And then they start running faster.


It starts raining heavily right before they reach their house, so they're soaked when they reach it. They laugh, amused by their bad luck. They go to their room to dry off, after they greeted their parents.


“hey...” Mukeiko suddenly mumbles somberly “It’s been seven years, huh..?”


“yeah.. But big bro wouldn’t want us to linger on it right? Let’s just live on.” Nico replies, looking away. “we’re training tomorrow again right?”


“yes… let’s do our best. UA entrance exams are available to us next year. The beach right?” Mukeiko asks “I still wonder what cleared it two years ago?” she ponders


Upon a change of topic Nico clearly relaxes and she replies “I dunno? Well actually, I heard that a crazed green haired boy did it? Maybe he was training too?”


“Surely. Well. I’ll go get cleaned up for dinner. Be back in a bit.” Mukeiko states, before leaving the room to go do what she said she was going to do.


Chapter Text

“MU-MUUUU!! WAKE UUUUPPP!!!!”, Nico shouted, jumping to land in Mukeiko’s bed-like construction, trying to wake up her twin. While she landed and splashed in her twin’s residual ink, Mukeiko’s core wasn’t in the bed. “Mu-Mu?”, She asks.


“Yes?”, came from the bathroom, “what is it?” Mukeiko pokes her not yet fully-formed head into the twin’s bedroom.


“You’re up already?! And to think I woke up way earlier?”, Nico pouts, “I really thought I’d be up earlier than you this time...”


“You know that’s near impossible if you want enough sleep right?”, the reply sounds, “don’t you remember I only need to lose my form and… I guess sleep? For a few hours, granted. I wake up generally around midnight. You remember this, right?”


“Oh. Right. Sorry! Well, shall we go? We gotta train early, before other people go to Dagobah and get in the way!”, Nico chirps, before trying to run out of the room. But before she could do that, her sister grabs her.


“Have you forgotten you can’t train in your sleepwear?” the inky sister points out.


“Oops, right!”, Nico bashfully exclaims, rubbing the back of her head.


While Nico gets ready, Mukeiko picks up the remaining ink in her bed, cleaning it up.



When the twins are done with their morning routine, they rush to “their” part of Dagobah beach, hoping to get as much training as they could in before the real crowds arrive.


“C’mon sis you won’t catch up to villains if you’re as slow as this! ~Go~fas~ter~!”, Nico sing-songs teasingly, speeding up her run. Mukeiko seems to be having difficulties keeping up.


“W-wait up..!”, the inky twin replies, looking as if she’s melting, “you know I’m not as fast… I need to focus on not melting..!!”, she pants.


“Oh! Right!” Nico slows down and turns around, running backwards. “We need to work on that!”, she giggles, turning back around. “Now, come we’re here…? Who the fuck is that?!”, she suddenly exclaims.


~ * ~


This boy was standing where the water should be, if it wasn’t being pushed away by the wind and air moving around the boy. This same air seems to be holding up the boy, who’s leaning backwards in a way that should’ve caused him to fall. He seems to be concentrated and peaceful. The boy has messy dark gray hair and pale skin. The piece of his outfit that stands out the most is a red scarf, as next to the red of this article of clothing, he wear mostly neutral tones.


“OI! WHO IN THE FUCK ARE YOU?!”, Nico screams, quite loudly, startling the birds around her.


Next to her, Mukeiko facepalms. “Oh dear...”, she murmurs, familiar with her sister’s antics.


Startledness appears to not be limited to birds, as the boy falls over with a loud “Wa-AH!”


“Oh dear..”, Mukeiko reapeats, now out loud, as she runs over towards the fallen boy. “Are you allright?” She checks the boy over.


“Yes”, the boy says, glaring coldly at Nico, “no thanks to that girl over there though.”


“Hey! I was just asking a question!”, Nico whines in reply, puffing up her cheeks.


“By shouting?”, came the short reply.


“Yes!”, Nico exclaims, “you were far away!”


“Quit shouting…”, the boy deadpans.


While this squabble between the two teens is going on, Mukeiko is standing in the background awkwardly. That is, before she decides to act against the unfolding argument, stretching her arms around her sister’s mouth. This in turn causes a gurgle of “Blegh, ink”, to come out of the now entangled Nico’s mouth, through the ink keeping her captive and, -to the strange boy’s great satisfaction- effectively shutting her up.


“Can we please not fight with someone we just met?”, Mukeiko pleads with her twin, after which she removes her arm from her sister’s mouth


“He started it!”, her sister whines.


“You startled me.”, the boy chimed in dryly.


Before Nico can reply to this, Mukeiko starts speaking: “Ah! Right, sorry for that…!”, She mumbles awkwardly.


“Anyways… uh…I am Sumitsubo Mukeiko. This is my sister Nico”, Mukeiko says, changing the subject, “Can we know your name...?”


“…” The boy stays silent.




“…” An awkward silence comes into existence. Everyone looks across to one another for a brief moment, until Nico, who at this point was getting annoyed, breaks the silence with a frustrated grunt.


“Whatever… c’mon Mu-Mu, let’s go train.”


“All right”, Mukeiko replies, before turning to the boy and asking: ”You wanna join us? It might be nice to train with someone of who we don’t know the Quirk…”


“Wait, before that, are you okay with that, Nikkun?”, Mukeiko says, interrupting herself by asking her sister this question.


“Ok.” both the boy and Nico reply.


“What is your Quirk anyways?”, Mukeiko asks, switching her mouth and eyes back to the side of her head visible to the boy. “Is it wind manipulation?”

“…” The boy stays silent again.


“Aaaallrighty, then”, Nico drawls “We’re not doin’ another awkward silence. Let’s start warm-ups or something!”


After she says this she starts doing stretches. “Let’s do a run across the beach after stretches. Like…uh… to that beach…house…dock…thing!”, Nico proposes. “If Windy wants to join us he’s free to!”, she states afterwards, seemingly calmed down from her frustration. “You okay with that Mu-Mu?”, she asks her sister.


“Uhhh…yeah…!”, Mukeiko replies as she starts stretching her body to silly lengths.


Now dubbed “Windy”, the boy looks at them both, before also starting to stretch.


~ * ~


“Weelllll then~”, Nico hums in a obviously improved mood, “I think I’m warmed up enough! ~Let’s get to running!~” She giggles and takes off.


“Nikkun, wait!”, Mukeiko yelps as she runs after her sister. Windy follows too.


As they’re running, the boy starts gaining on Nico. She notices this and she starts speeding up.


About halfway to the beach-house Nico is actually quite far in front of both her sister and Windy. She looks back slightly and starts to open her mouth to speak but…




She smacks against an invisible wall and falls on her butt, yelping in pain as she does so. Mukeiko runs up to her sister in worry, checking if she’s okay. Nico seems fine aside from a bump beginning to form on her head, and slightly dazed behavior. Windy touches the wall, looking at the seemingly empty air with an apathetic expression.


What even?!”, Nico sputters, cradling her head after shaking off the slight daze she got. After deciding the wall is most likely caused by a Quirk, she starts looking around to find where the one making the wall is. Finally her eyes land on a person a little to the left of the group. The person is, most likely, a boy, with his arms stretched out in front of him and his palms angled out. Most of his features are obscured by an over-sized hoodie.


As the kid finally processes what has happened he dropped his arms, yelping an apology and running up the stairs, then away. The moment he dropped his arms the wall disappears.


Hey! Wait! You!”, Nico shouts after the newcomer, hopping back up on her feet and chasing after him. “WAAIITT”, she screams after him. Seeing him turn a corner, she speeds up a bit. Her sister and the other boy, in turn, chase after Nico.


The group of three dash after the kid, only to see him take another corner.


And so they continue, turning corner after corner, going into the city, nearly catching up a few times, until…


There! That’s a dead end!”, Nico exclaims in victory, running into the side alley she saw the kid take. “He should be…! Huh?!” She cuts herself off, startled, as the other two also arrive in the dead end, only to find that the kid disappeared. “Where’d he go?!”, Nico squeaks with a startled face.


Are you sure we turned the right corner?”, Windy says, bluntly.


Yes! I’m not blind”, Nico sputters, “where’d he go…?”


Mukeiko looks around for a bit, and then speaks up. “He might have taken that ladder up.”, she says, pointing at it, “he seems fit enough to reach it.”


We should, however, get back”, she states after a small pause. Immediately afterwards she softly mumbles another thing: “There’s no reason to be chasing the poor kid anyway.”


Fiiiine”, Nico whines before stretching her body, “Oh, well. It was a good warm-up!”


Let’s go then”, the boy grumbles, as he turns to walk back to the beach.


The other two follow him.


~ * ~


As they return to the beach, Mukeiko speaks up: “You guys can begin sparring. I…want to practice how to manipulate my body whilst not melting.”


That’s fine!~”, Nico hums, “I wanna see how this guy fights!” She turns towards Windy and takes on her fighting position. “Let’s do a round without quirks first!”, she proposes.


Sure, why not?”, the boy sighs in reply, “well, then, three” ,he begins to count down.


Two” Nico chimes in


THREE!!” And as she shouts this, Nico charges at the boy, keeping low, while the boy prepares to intercept her. Nico kicks high, towards his face. But he grabs her leg, holding her in place momentarily before pushing her away and backing up.


Is that all?”, the gray-haired boy taunts Nico, awaiting her next attack.


Hey!”, Nico hisses, as she runs to attack him again, trying to kick his stomach this time. The boy manages to dodge this easily, getting behind her. This in turn causes Nico to stumble, as she had expected to hit. Taking advantage of the situation, Windy shoves Nico, causing her to fall down in the sand and yelp in surprise. He also tries capitalise on this, but Nico rolls away and trips him. It works! As he tries to move away, he gets hit and falls down, while she gets back up and tries to stomp on him. However he curls in on himself, and, like a spring, unfurls and gets up. However, Nico dodges away from getting hit by this.


It goes on like this for a while, trading blow after blow, falling down, and getting back up. With Windy keeping back and holding her at arm’s length, taunting, while Nico closes the distance, getting more and more frustrated and growing more and more exhausted. This continues and continues, until…


Nico shrieks in frustration as she runs low and tries to punch the boy. He easily dodges this now sloppy move and Nico misses, runs past, and turns around panting. The boy now makes the first move, rushing the exhausted Nico and kneeing her in the stomach, making her fall. She doesn’t try to get back up.


You win”, she pants with a smile on her face, “Maann”, she groans, getting up. “I haven’t had such a tough fight in a while, no offense, Mu-mu!” she shouts, while also getting the expected reply: “None taken”, from Mukeiko’s direction.


The boy grunts in reply.


Well. I’ve seen your quirk and you’ve seen my sister’s”, Nico mutters, “but you’ve never seen mine so…” Nico takes out a sketchbook and turns to a page with a drawing of a ball “Hmmm… half an hour should be fine...”, she mutters, before ripping out the page and holding it close. After a bit she throws it and it turns into black ink, which then grows into a sphere. This sphere then starts adhering to the laws of gravity, and falls down to the earth. And now there, in the sand, lays a ball, an exact copy of that which was drawn on the page. If you were to look at Nico’s hair, you’d notice that her roots turned blonde.


Well there we go, that’s my quirk.”, Nico says, “I can make things come into existence for a limited amount of time. I just need to draw them accurately.” She picks up the ball she created and throws it towards the boy. “I’mma practice my quirk now. You can use these.” Nico settles comfortably on the ground. “Come to me when this one runs out.”


And so they begin training. Mukeiko stretching, Nico drawing flowers and popping them into existence, making the black in her hair recede, and the boy floating around the ball.


And so they spend the rest of their time. As the first ball returns to paper, Windy gives it back to Nico in her garden of flowers, constantly popping in and out of existence. Nico now pops two of the balls into existence, one from the paper the boy returned.


This routine continues until Mukeiko speaks up: “I think it’s time to go home, Nico. The sun is going down.”


Yeah, true.” Nico says. She then adds: “We should wait till every creation poofs, though. I don’t wanna litter.”


As they wait, Windy speaks up: “Kazehana.”


Huh?”, Nico replies in confusion.


My name. It’s Kazehana Asio. You asked for it right?”


Oh! Right! Well, it’s nice to meet youm Kazehana-kun! My name is Sumitsubo Nico, and this is my sister Mukeiko. Let’s get along!”


Yeah…” the boy formerly known as Windy, now known as Kazehana, mutters: “Let’s get along, then, Sumitsubo-kun. You too, Sumitsubo-chan. See ya round, I guess.” Kazehana then turns around and walks off just as the last objects pop back into paper.


“See ya!”, Nico screams after him, while Mukeiko chimes in with a quick “Farewell!”, after which both turn around and start picking up the pieces of paper, wondering if they’d see their new friend tomorrow too.


Chapter Text

“ ‘Nother day, ‘Nother set of sleepy,” Nico mutters unhappily, rubbing her eyes. “Why do I have to know who wrote this-or-that book?” She looks to her sister, Mukeiko, who is not entirely listening to her grumbling. Rather, the older girl seems to be scouring the beach.


Huh? Whatcha lookin’ at, Mu-mu?” Nico asks, as she realises her sister’s attention is somewhere else.


Mukeiko mumbles slowly: “I’m trying to see whether or not Kazehana-san and that other boy are here again,” before widening her eyes, and blurting out: “There!” pointing to where the by now familiar figure of Kazehana Asio can be seen.


The other kid ain’t here, is he?” Nico asks. She then mutters under her breath: “I wanted to have a word...”, before taking a breath and screaming: “OI! WINDY,” making Kazehana fall into the water…again. Mukeiko glances, exasperated, at her sister.


The poor boy gets up angrily growling: “Really? Again? Why am I even surprised?” Rubbing his face, the twins come near him and he continues: “Can you not screech like a fucking banshee for once?!” As the girls approach him he gets up and adds: “And my name isn’t “Windy”, Blondie,” as an afterthought.


Nico only heard the insult. “BLONDIE?!” She fumes internally for a brief moment before regaining her composure and saying: “Can’t even be creative! Try again!”


Uhm, what?” he responds, flustered, and cocks his head at Mukeiko.


Y-You know what I mean!” Nico replies, waving her hand at him.


Uh, n-no?”


Try again! With the insult! Blondie is just so, so…cliché!” Nico, quite proud of the big word she just used, is now just whining without a goal, free from all logical thought. As she opens her mouth again, Mukeiko wraps her arm around Nico’s lower face.


Ignore her, Kazehana-kun… she does this every once in a while. She can’t stand when others don’t match her creativity,” Mukeiko sighs, before shifting her eyes further to the side of her head to look at her sister, still blubbering words into Mukeiko’s arm. “Have you calmed down any, Nikkun?” At the ensuing gurgle, she removes her arm, looking towards Kazehana.


Do you want to train with us again?” she shyly asks him to which a simple “Fine,” serves as reply.


So let’s run again, already! Race ya, Windy!” Nico shouts exuberantly, before promptly taking off.


Hey, Nikkun! Wait!” Kazehana replies.


You can’t call me that!”


And so begins another day of training.





After going through the same song and dance as the previous day, Mukeiko goes to ask something of Kazehana, standing near the edge of the water. “Excuse me? Uh…Kazehana-kun, do you want to spar with me?” she says, poking her fingers together rhythmically.


Sure,” He replies curtly. “Are we using Quirks?”

O-of course! I can’t turn mine off after all...” Mukeiko says, somewhat awkwardly, before getting into something of a combat pose, forming large claw-like hands on her arms. Kazehana takes on the pose he had used the day before.

Good luck Mu-mu! Kick his ass!!” Nico cheers in the background, summoning a set of pom-poms for a second to strike a pose.


At the count of three the combatants begin fighting, Mukeiko stretching out her arms towards her opponent, trying to tangle him, but a sudden wind thins them out. Mukeiko pulls back, and launches a frontal swing. At this action Kazehana reacts by manipulating the air around him in order to block her from reaching him. This causes her claws to be reflected away with some ink flecking off. Mukeiko backs up, her claws moving into a defensive position.


That…didn’t work as I wish it did,” she mutters under her breath. Then, suddenly, she goes in close. A strike aimed for the throat.


But it doesn’t connect. Mukeiko is sent flying to the sea by a gust of air. A good chunk of her body falls off, but she lands on her feet, mere inches from the water.


And so it continues. Mukeiko gets no hits in. Blown away time and time again, she is growing obviously distraught by her repeated failures. Though it would be apparent to any onlooker that Mukeiko will not win, Nico keeps encouraging her from the sidelines.


A splash resounds.


Mukeiko has landed in the sea.


MUKEIKO!” Nico shrieks, rushing to her sister’s aid, eyes widening in panic. At the same time, Mukeiko is trying to escape the water, but is being quite hindered by her seemingly melting limbs. Before Nico can get close enough to help, the inky sibling’s body gives out, spreading out onto the water like blood.


A small, white orb rolls out of the puddle of ink. Nico picks it up with both arms, sighing in relief of having recovered it.


Thank fuck you didn’t get washed away, huh?” she says to the orb, as she walks to her bag and begins to rummage in it. The orb vibrates as if to respond to her question. She keeps fishing in her bag as Kazehana runs up to them.


What just happened? And what is that thing?!” He asks, his voice startled and his eyes widened.


Don’t worry, you didn’t kill her,” Nico reassures him, finally appearing to have found what she was looking for. “This is pretty normal.”


That’s…Mukeiko? How is that normal?!”


Quirk,” Nico shrugs, as she pulls out a bottle of ink. “This ball, well,” she states as she pours the ink over the orb, “It’s Mu-mu’s real body.” The volume of the ink seems to expand, as it form into a small rudimentarily human shape, no bigger than a toddler. Kazehana blinks in surprise.




What’s not to understand?” Nico taunts. “Quirks are weird. Now, are we just gonna stand ‘round like a buncha fools, or are we going to spar? Mukeiko needs to regain her size, anyway, so you can fight me now,” she says as she takes on a fighting stance. Kazehana hesitanty copies her, and they begin their own round of sparring.



This goes on in much the same way during the remaining weeks before the entrance exam. And as the girls are ready to leave for it, Mukeiko pauses to look at a picture of their brother.


Hey… Nikkun?”


Yeah? What?”


Can we visit big bro’s grave before we go to the exams? I want to tell him we’re close to making it.” Mukeiko sighs “We don’t hav-”


We can do that,” Nico cuts her off, smiling sweetly, “if it would make you feel better?”


It would…thank you.”


Let’s go then. Don’t wanna be late.” Nico turns to walk through the door. “Hurry up, slowpoke,” she says, already back to teasing her sister, who follows her.



About a half an hour later, as they arrive at the graveyard, Nico stops at the gate and hands Mukeiko the flowers the smaller sister picked on the way there. “Here.” Mukeiko looks at her quizzically “You should have a moment alone with…him. I’d rather not.” Nico starts stretching to keep her muscles warm, as Mukeiko nods to acknowledge her sister’s preference.


Alright, Nikkun. I will be right back.”


A good bit later, Mukeiko returns, and the sisters walk, uninterrupted, to the UA grounds. Both are silent. After a few minutes, Nico pipes up.


So, this is it, huh? You better not bail out.”


I would never. We are going to be side by side for the rest of time. Let’s make big bro proud!”


Make everyone proud. We’ll get in, I’m sure of it.” Nico looks up to the gate. “Wonder if Windy is here too. Heh, prolly,” she sighs, brushing her hand against her sister’s arm.


...We should hurry inside. It’s cold out here.


Then don’t wear a t-shirt in february...”


Oh shaddup.”