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A Demon's Shadow

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With silent steps, quick but careful, Oni made his way through the alley way, sticking to the darker shadows and moving quickly. He didn’t make a sound, carefully keeping silent, senses spread. It’s too dangerous to allow any missteps or miscalculations. 


Pausing, Oni slid to lean against the wall, only briefly groaning internally about washing his suit when he gets home. There were sounds of a fight, subtle and muffled grunts, cut off pained noises, and while it could be something else, he doubted it. Oni has been a vigilante for years, and he would bet on a fight.


“-Ah ah ah, I wouldn’t do that if I were you.” A voice, amused and slightly annoyed, seemed to echo the alley unnervingly.


There was a screech that cut off quickly. “I warned you, didn’t I?”


Shifting closer to the corner, Oni peeked around the edge, careful to keep quiet.


“What? Done already? Come on, I’m not done playing!” The one talking was wearing dark clothing, hard to tell what it was, and a hood with a black mask with a white grinning mouth painted across, no visible eye holes or anything. There was something childish but unnerving about their words.


A Hero? No, no, had to be a vigilante. Heroes had a code of ethics or morals they followed.


“Did you pass out?” The masked person asked, genuinely confused, kicking the downed man, but getting no response. “Oh, dead. That’s boring.”


Villain, must be. Most Vigilantes didn’t kill, or at least tried not to kill, Stendhal… was an entirely different matter.


“Who’s there?” They suddenly called, and despite himself, Oni’s heart rate skyrocketed, before forcefully calming himself down.


He didn’t respond, but he did reveal himself, seemingly melding from the shadows.


“A hero? No, you aren’t one I recognize. Vigilante then.” The masked killer said, voice tinged with curiosity. Turning to face Oni fully, they laughed. “I haven’t met you before! New to the town? New to the business?” They asked, standing, the long dark fabric of their clothing swishing around the back of their legs like dancing shadows.


Gritting his teeth, Oni remained silent for now, unsure of their quirk or intent.


“Were you after him as well? A little late to the party.” They said, nudging the body with their foot, black boots far from gentle. Oni narrowed his eyes behind his mask, activating his quirk, but they didn’t show any sign of noticing or being bothered by it.


Either non combative quirk, or one that wasn’t something they depended on.

Or very good at controlling their emotions.’


Oni shifted forward, prepared to fight, and the masked killer didn’t even seemed phazed.


“Just going straight to fighting? Most other Vigilantes I met at least asked questions first.” Oni’s eyebrow twitched. Mockingly bowing, the killer gave off an air that they were amused. “We haven’t met, trust me, I never forget meeting someone. Except Handsy, but it all worked out, I eventually remembered him…Well, not his name. That’s fine, we mostly try to kill each other anyways. Who needs names when you got a knife towards the gut and a hand for the throat, right?” Rambling, they waved at Oni, who launched forward at the movement, only for the killer to duck under his fist. They laughed, even though there was a dark air about them that had Oni’s instincts blaring warnings.


“Quick, aren’t you? Definitely not new to the business.” They said, laughing as they dodged a kick, and leapt back from Oni when the vigilante lashed out with a staff. “Well, it is Musutafu, new faces everywhere in new places, right? What’s your name, vigilante?” They asked, voice full of excited amusement, and despite their cheerful demeanor and drifting topics, there was something unsettling about them.


“Why should I tell you?” Oni growled, growing more irritated by the minute. They laughed again, lashing out with a kick that Oni had to jump back in order to dodge. 


“I can always just give you a name myself, though I’m not sure you would like it! Handsy didn’t like the name I gave him, but his fault for not telling me his name. Now I can’t be bothered to learn it.” They said, bouncing on the soles of their feet, never quite sitting still, and seemingly blending with the shadows of the alley, long coat, for thats what must be trailing behind them since a cape is just illogical, swishing around their legs and blending into the shadows almost perfectly. If it wasn’t for Oni’s mask, designed like a demon but enhanced with tech, Oni would have a harder time keeping track of their movements.


“I don’t need a villain to know my name.” Oni snarled, lashing out again, but the masked killer continued to dodge, and they were left in a stalemate, neither getting any hits in, or covering ground. They held a gloved hand to their chest, seemingly offended.


“I’m not a villain! Rude!” They definitely were offended. Oni stopped attacking, but didn’t relax his fighting stance. “I’m not a hero, but I’m sure you guessed that. Heroism isn’t fun at all, not with all the rules and morals that get in the way. But villainy isn’t all that great either.”


“Who do you think you are?” Oni demanded, losing patience, and the killer laughed, motioning to the body on the ground.


“I’m free from society's labels, hero, villain, vigilante, whatever. I am the judge, jury, and executioner .” They said, throwing their arms out, and suddenly, they were right up in Oni’s face, unsettling painted grin so close.


He hadn’t even seen him move!


Oni’s reflexes weren’t even quick enough to keep up with the speed of his opponent, he could only widen his eyes, quirk flared.


They call me Kage. ” And then, Kage slipped beneath Oni’s instinctual punch, and around the vigilante. When Oni whirled around heart thundering in adrenaline and fear, they were gone.


Neither hero, villain, or vigilante.


Oni turned back to the body, and there was a black note card on it, Kage left printed in white on it.


Then sirens sounded in the distance, so Oni made his way home, taking the roof tops, thoughts plagued by the new variable in the equation. Kage, arrogant but talented.


And vicious, Oni glanced back briefly to the alley, but continued back to his usual patrol area.


He isn’t sure he wants to meet them again. A person skilled in hand to hand, that was fast and without using a quirk as far as he noticed.


Oni is unsettled, because he doesn’t know what their quirk is, and while he had his quirk active, it didn’t seem to bother Kage in the slightest.


Kage was dangerous.


He would looked up information on Kage when he got home, and do his best to avoid them.

Situated on the roof across the street from the alley Oni had left, Kage sat.


“A vigilante, with eyes like that…” Kage muttered, grin curling his lips beneath his mask as he held a hand to his cheek. “ How exciting. ” Standing up, Kage paused, looking down at his hands.


This feeling…


He hasn’t felt like this before, full of excitement and anticipation.


He’s never felt more than his usual bored apathy and brief stints of battle fueled adrenaline.


Looking up again, he looked off to where Oni had headed toward.


That vigilante…’ Kage thought, a deep excitement and almost overwhelming anticipation that seeped through his veins like fire.


Taking his mask off and grinning out over the city, he laughed, throwing his arms out.


“I want him !”


He wouldn’t forget the fire in those eyes, glowing red as they stared him down.


He had to have him .


Kicking the door closed, Oni slid to sit on the ground, back to the door. Shakily reaching up and pulling his mask off, he took a shuddering breath. Kage’s aura, the swift and nearly overpowering feeling of dread that hit him had sent his instincts haywire.


It reminded him almost of Stain.


It was sudden, and gone just as quickly, but Oni recalled the split second it appeared, right when Kage had slid right into his space, and true fear had swept through him because there was no stopping a killing shot or incapacitating blow.


Then it had vanished, like Kage did.


He almost threw his mask, but instead let it slip from his hand and to the floor, it was difficult to get tech like that as a vigilante.


“Kage…” He muttered, dark eyes blazing red as he subconsciously activated his quirk. Black hair fell into his face, long and messy, as he grinned a slightly hysterical smile. “How terrifying.


He’s shaken out of his near hysterical moment by Mochi, his fluffy and chubby white cat, yowling loudly at him. Huffing, his quirk stopped and he threw them a fond but exasperated look.


“Calm down Mochi, I’ll feed you in a moment.” Running a hand through his hair, he breathed out slowly, tense shoulders relaxed. Standing, he shook himself and picked up his mask, setting it on the counter. He won’t let it get to him next time, he shouldn’t have let it get to him at all.


He wasn’t new to being a vigilante, and Kage wasn’t the first dangerous person he’s met.


But the feeling I got from Kage was unnerving, worse than anything I’ve come across before.


Aizawa decided to not think more about it. He’d be more vigilant next patrol.


Mochi yowled.


“I’m coming, stop whining.” He would browse through Yoogle later to find as much as he can about Kage. A dangerous person like that had to be talked about online.



Humming, Izuku skipped up the stairs to his apartment, unlocking the doors, he nearly danced inside, still riding the excited rush he felt from meeting the vigilante. Laughing breathlessly, Izuku threw his duffle bag onto the couch, rolling the sleeves up on his button up, Izuku happily made himself dinner. It wasn’t until he was putting the dishes on the drying rack after dinner that he realized he was still giddy and nearly vibrating with excitement to see the vigilant again that he might be a little too excited.


The world hadn’t returned to its bland, almost overwhelmingly boring self.


Pausing, Izuku grabbed a rag to dry his hands as he leaned against the counter, trying to think about what he was feeling.


Face warming, Izuku hummed.


He might have a crush…


Eyes widening, he recognized the way he felt, he seen it growing up all the time.




That had to be what this was, this encompassing feeling of excitement and anticipation to see him again. It was almost addicting, this feeling he has. It’s not just the thrill of an exciting battle, Izuku’s felt that before, however brief it that usually was.


He may have never been in love before, but this must be love, love at first sight.


His mother feels this way about his father, so it must be that, he’s seen the way his mother looked at his father, how she waited eagerly for his every call.


This is something deeper than a crush, or desire to fight again.


Tossing the rag onto the counter, Izuku headed to the living room, digging his phone out of the duffel bag, he ignored the texts from coworkers, questioning about plans and some random things of their day, he’d answer them later, right now, he had to call his mother.


She would tell him if he was getting ahead of himself, she was always understanding of the way he just.. Struggles to experience things like other people. She was always patient with him, and explaining things to him. 


After all, this type of apathy runs in her side of the family, but unlike him, she had his father who brightened up her life, who made her feel powerful emotions.


“Hey mom, it’s been a while.” He said when she answered, content, but despite that he probably should get caught up with her, he was more interested in finding out if she could help him.


“Hi Izuku! You haven’t called in a while!” She chirped, and he could almost picture her smiling. “Yeah, work has been busy, but I’m not calling to catch up right now. I met someone .” Izuku said, excitement coloring his voice, and he could hear his mother’s hum of interest, he didn’t have much time to talk to her, his father usually calls around this time so he had to be quick, he knew his mother waited on those calls, proof that her husband loved her and was thinking of her all the time.


It was what they agreed upon when the offer to work abroad had came up.


“Oh? Did you finally find someone?” She asked, and Izuku couldn’t help the grin that spread across his face just at the thought of his vigilante. Imagining him, all fierce looks and the excitement of their brief battle stalemate, and he could feel that excited rush return full force.


He feels alive .


“Kinda, I think I’m in love mom. We only just met, but it was amazing mom! He was so cool! Serious, and a little dark and broody but that only made him more interesting!” Izuku rambled, finding himself more and more interested in his vigilante, and his mother only seemed to encourage it. “He had such a serious attitude, and he had such an amazing look in his eyes, I want to see him again!”


“Ah, Izuku, baby, you sound just like me when I first met your father.” She sighed wistfully, and he couldn’t help the excited bouncing. His mother’s first and only love, Midoriya Hisashi.


 His mother and father met in high school, and it was love at first sight. His father was devoted to his mother, calling her several times a day when he got the chance to tell her about his day, how much he missed her and loved her, having to hear about her day, if she missed or loved him.


He wanted that, he realized, with his vigilante.


Just imagining them like that-


He wanted him .


“Mom, I want him. I have to have him, to have what you and dad have.” Izuku said, honest and almost desperate, the desire to have the vigilante his almost swallowing him whole, the world was so much more vibrant than the bland existence from before.


He was becoming obsessed.


His mother only giggled, before parting with some advice.


“Keep calm, not everyone will like things demanded of them, and have to take time to realize they need you. It took me months to win your father over, and make sure no one else would have the chance to steal him away. Small things Izuku, small things. You have to make sure he falls in love with you, that he won’t look at anyone else. Now, before your father calls, let me tell you a few tips, with how I won your father over…”


Izuku memorized everything she told him, determined to make sure that one day, he’ll have his vigilante.


Have the one who makes everything interesting and exciting again.


“I have to go now Izuku, your father will call here in a few moments, and you know I can’t miss his calls.” His mother said, giggling, and Izuku smiled to himself. “Alright, goodnight mom.” He said, and she returns his goodbyes before hanging up.


Staring at his phone, Izuku put a hand to his blushing cheek.


He’ll find out as much about his vigilante as he can, to better protect him.


He settled down to look into as much of the vigilante as he could find.


He’d answer work texts later, if it was an emergency, Sansa would call, besides, he’s only been on the police force for three years. He’s not very high up the ladder, despite the moments where his analysis is needed.



Aizawa shuddered slightly, rubbing his hand against his neck as if to ward off the chills not brought on by the cool air. He sometimes swore he could feel he was being watched, and the following months after meeting Kage, he felt more paranoid.


It felt like almost everywhere he went, there were eyes on him.


It was unsettling.


He was confident that no one knew his identity as Oni, he had a job he did during the day and he made sure to backtrack and double over the places he walks to confuse or lose any possible followers.


He was very cautious to make sure he wouldn’t be identified as Oni.


He paused, there was a police officer across the street, bright grin and curly green mop of hair, he was talking to a girl, a teenager possibly, and there were an ambulance and crime tape up, he made sure to stay with other onlookers to seem like another curious civilian.


There were other police officers walking around, some keeping too curious onlookers back, others pointing and directing others, a few paramedics made their way into the alley way.


The curly haired officer managed to calm the girl down, and briefly looked up.


They made eye contact, and Aizawa almost blinked in surprise, but managed to keep a hold of himself. The officer looked back to the girl he was most likely getting a statement from, and Aizawa carefully continued on, briefly glancing over at the alley, wondering what the crime scene was about.


He barely caught a glimpse of a hand falling from beneath a sheet as some paramedics carried a covered body into the ambulance, slightly making out the rushed and concerned paramedics calling out orders to each other, no doubt trying to save the person’s life.


He continued on, briefly thinking back on the scene.


Maybe he’ll take a look around tonight, see what’s going on.


Though, the curly haired officer was pretty common around now, he must have been moved to the station nearby. A graduate? Maybe just an officer pulled in from a different station.


Right now, Aizawa has to get to the bookstore, he doesn’t have time to waste wondering about the officer, when his shift at the store starts soon.


He chose it specifically because it’s quiet, and not many stop by too often, usually just to read a bit, or get a book, occasionally to drop off a few.


Occasionally a few people stop by on break, picking up coffee or something from the cafe a few buildings down, then stopping in the bookstore to read


“Ah, Aizawa-san, just in time!” Aizawa blinks, turning to look at his coworker, Hiyaji Kaito. The man was noisy, but knew when to quiet down. His quirk, Memory Bank, lets him store memories with perfect clarity, and pull them back up, recalling the memory as if it happened only hours ago, instead of how ever long ago it truly was.


It’s a big help when memorizing where all the books go, so it’s easier to make sure the books are in the proper place, and can be retrieved just as easily.


“Obviously.” Aizawa says in lieu of greeting, Hiyaji unfazed by Aizawa’s disinterest, cheerfully ignores the flat greeting. Pausing, Hiyaji leans close, frowning, and Aizawa stares back flatly.


“You been sleeping alright? You look awful.” Blunt as always, Hiyaji doesn’t even stop to think if his words may be rude or not, a side affect of his quirk’s perfect memory and recalling of memory, it makes him very blunt and more likely to accidentally offend someone because he can’t really process what he wants to say very easily.


“I sleep enough.” Aizawa says, walking around his coworker to put on his name tag and uniform, Hiyaji following, unbothered with keeping an eye on the store, their coworker for this shift, Naka Kaho would keep an eye on it all, quiet and largely uninterested in anything beyond finishing her shift and going home.


“I don’t believe that, especially since your eye bags scream ‘What the hell is sleep?’ and are big enough to carry groceries.” Hiyaji responds, tone tinged with exasperation. Aizawa sends him a glare, unamused. Hiyaji only casts one back at him.


“I… I just feel paranoid lately, I’ll be fine.” Aizawa huffs, pulling his uniform on, pining on his name tag, before stalking out to the cash register, Hiyaji close behind. “So you say. Are you okay? Do you need a place to crash? I’m sure Sacchan won’t mind if you crash at our place, they might pretend to be all grumpy, but it’ll be fine.” Hiyaji offers, and Aizawa pauses just briefly enough that Hiyaji notices, despite already shaking his head.


“It’s fine.” Aizawa says, though he will admit to himself he almost took Hiyaji up on his offer. Though, Aizawa doesn’t find it necessary. He has years of vigilante experience under his belt, he should be able to defend himself if necessary. 


That, and if he does have a stalker, it won’t be safe for Hiyaji or Sakuya, his partner. No normal person would stalk him, but even if someone did , he knows from stopping stalkers as a vigilante just how dangerous they can get.


“Aizawa.” Hiyaji stops the dark haired man, holding his shoulder. “I’m serious, if you need a place, or anything, call me, me and Sacchan will happily lend you our couch.” Aizawa nods, and after a moment, Hiyaji sighs and lets him go.


“Alright, let’s get to work before Naka-san glares at us the rest of her shift.” Hiyaji says, quickly making his way to the book carts to start putting the books on the proper shelves. He has a healthy fear of Naka, the woman is quirkless, but a mutation from a quirk at some point in her family line makes her eye color almost white, and it’s unsettling paired with her unimpressed and almost judging look.


Aizawa sighs, and settles in for work, already prepared for a long and boring day.


‘Better than some busy, loud job. ’ He thinks, pulling a book from beneath the counter, the small dark blue bookmark sticking out letting his coworkers know he’s reading the book. Each worker has specific bookmark that they place in the books they read on slow days during their shift. No one messes with someone else's bookmark or book, lest they bring the wrathful and scathing looks the other workers will send them.


He’s almost finished with this book, when he gets chills down his spine. He glances up and around, most people reading or browsing books, Hiyaji is humming some tune down the mystery isle, and Naka is straightening some couches in the reading area, no one is looking at him, and no one suspicious is hanging around.


Why am I so uncomfortable?’ Aizawa wonders, sharp eyes looking around the shop, eyeing every person and corner, looking for whatever is giving him chills. It reminds him of the feeling he gets sometimes out on patrol.


And it isn’t a good thing, since usually following that feeling, Kage leaves…


Gifts , for Aizawa to find.


He refuses to think anymore on that.


The feeling abruptly disappears, only moments before the green haired officer steps into the shop. He’s going through a few manila folders, focused and a pen tapping his lip as he walks over to one of the window seats. He is focused on his work, but does glance up longingly at the shelves of books.


Aizawa assumes he’s on break, but doesn’t think much more on it, though his eyes do wander from his book to look upon the officer again.


He’s idly noting things about the man before he could catch himself, a habit from his patrols, scoping out people and suspicious characters. Though, he’s more focused on the officer, as the curly haired man is becoming a regular officer in the area.


‘Is his hair green or black? It looks soft. His eyes are really green, is the coloring something to do with a quirk? Is it a passed on genetic mutation from a grandparent or ancestor's quirk?’ Its small observations he does for particularly interesting customers, or during his patrols, though usually more to gauge opponents before engaging, a habit he has no need to break.


The officer checks his watch, and apparently decides he has enough time to browse for a book, quickly gathering his things and heading off for the shelves. Aizawa notes he heads down nonfiction, specifically medical texts.


Gone from his sight, Aizawa returns to his book, and slowly gets lost in the tale.


He’s disrupted by the officer, who now looks slightly frantic, bouncing from foot to foot, a book on quirk theory and an advanced medical book on the body and quirk alterations effects on it.


“Just these?” Aizawa asks, bookmarking his book and setting it to the side, and the officer nods, glancing down at his watch as Aizawa rings him up.


‘His eyes are a brighter green up close.’ Aizawa muses subconsciously, before quickly clearing that thought away, ringing up the books and checking the total. The officer is smiling nervously, folder tucked under one arm, and pen in his shirt pocket, his radio goes off quietly as the officer pays.


“Thanks!” The officer chirps, turning and heading off before Aizawa can give him his change. The radio had said something about a robbery, or Aizawa assumes that was said. The officer, Mirdoriya the name tag read, is already gone by the time Aizawa finished counting his change.


He sighs and puts the change in the tip jar.


The officer fades from his mind.


Izuku hums under his breath to himself, books set into his bag, folder set aside as he heads to the scene of the robbery, he’ll mostly be keeping the crowd back, or questioning victims or witnesses on scene. He’s apparently good at keeping calm, and calming them down.


He does grin to himself, because he got to see his vigilante. It wasn’t easy figuring out his identity, or what he looked like. He was very cautious and managed to give Izuku the slip a few times.


That was good though, it meant he was safer.


He’s fine with shadowing his vigilante for now, getting rid of pesky villains targeting him.


But, he knows where his vigilante works, his name, and what he looks like out of his costume.


Izuku glances to the file, smile cheerful.


‘Getting popular, aren’t you Oni.’ He muses, a piece of paper sticking out of the file, Oni in bold letters.


He’ll make sure none of the police force figure out who Oni is, or how to capture him. It’s a good thing they call him in to help with Vigilante cases, his analysis is very helpful in situations like this…


And he has no qualms with using the police force’s trust in him to his advantage.


Oni’s identity will never be found out by anyone other than Izuku.


He’ll make sure of it.