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Kid for One

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Fear was a rare experience for All for One.

He may have gotten cocky in his younger years as he accumulated an arsenal of quirks and followers. But as his biological clock ticked, he was reminded that death was an enemy he could never outwit or outrun.

Until he discovered that there truly was a quirk for everything.

Eternal youth. Impenetrable immune system. Dozens of durability and regeneration quirks. He was essentially immortal.

Whatever happened to him after, resources or empires lost could always be recovered. His goals of a better society would be completed, it was only a matter of time.

It would be nearly another hundred years before he could feel fear again. Before he once again had something he could lose. No, someone.


When he first met her, it was an entire new spectrum of emotions. She was one of the few people that could still peak his curiosity. She showed kindness without ignorance. She was able to keep the supervillain entertained with interesting conversations.

Inko was clever. And while All for One still believed he was smarter, he couldn’t hide his true nature from her forever.

And with that, the fear had returned. What would she do when she found out? Would she turn in every last piece of information she had gathered on him to his enemies? Would she run and take away with her all those wonderful emotions she’d invoked in him? Would others find Inko and use this new special somebody of his to get back at him?

Inko was a weakness. That’s what his logical side told him. The side of him that clung on to power and kept him alive. The side that always planned 50 steps ahead.

But what was life without taking risks? Greed, that was a sin that certainly had a hold over him. He could afford to go after whatever he pleased with the kind of power at his fingertips. He could indulge in the few things that brought him joy when he knew there was little that could touch him. Maybe Inko would turn on him one day. She would certainly die. But to not enjoy his time with her while he could would be the real crime. He could deal with whatever fallout a betrayal may bring. And any pain from losing her would have to be something he’d move past. Better to have loved and lost than to never have loved at all, right?

Yet there was no betrayal. And she seemed to specifically not peek under the curtain that was the mystery behind her boyfriend that would eventually become her husband. The fear of losing her still occasionally lingered in his head. But it wasn’t as strong as the day it hit him that he was actually in love. That he once again had something to lose.

That was the trade off, wasn’t it? Pure joy and happiness in exchange for a vulnerability. But even if Hisashi hid his quirks, he would always be able to protect her. So long as she was willing to stand by his side, he wouldn’t let anyone harm a hair on her head.

Izuku made that all so much more difficult.

Not only was it another head to keep track of, but the boy wasn’t a fully functioning adult able to survive on their own. He was a squishy little child that could easily get sick, injured, and couldn’t even walk on their own. And even after only a few years, it was clear the boy had a reckless streak about him. Hisashi blamed the hero media he consumed like junk food.

Izuku would need more monitoring. And he would live a much harsher life being quirkless. Perhaps Hisashi could grant him a quirk… but only after his son had grown out of what he hoped was just a ‘hero phase’. No need to hand the boy the noose to hang himself with in that horrid profession. Maybe once he was 12 and had grown out of that obsession, Hisashi could grant him a nice safe and subtle quirk that would keep him from being discriminated against in the future.

All for One’s fears hadn’t been strong enough. The point of fear is a primal urge to keep you safe. And like in his youth, he’d grown too cocky. He didn’t see another wielder of One for All as a threat. He thought he could take care of them like swatting a fly.

All-Might took everything from him.

Physically, his body was in shambles. Death was once again a threat looming over him if he was unable to find a quirk to stop him from deteriorating even further. He couldn’t even wield half his quirks gathered through the years in his new state.

Those he could potentially recover. There was still hope.

But his family was lost to him. That was the part that made him want to make All Might suffer the most. He couldn’t face them in this state. Inko would think he abandoned her. He’d miss out on Izuku’s childhood. Perhaps he could try and keep his distance. Fabricate a story about going overseas. But there was no telling how long it would take to return. Years. Decades. The right quirk could take a while to find, and then there was the question if he’d even be able to use it or would need to be at the mercy of its original wielder for their aid.

With each year that past since the injury, fear’s grip closed around him. No one but his closest associates could see it, but All for One was getting desperate. Hasty. He was racing against his own possible demise. Every month that passed, his family slipped away from him a little further. He had them watched. But he could no longer be there for them. Not until he recovered.

All for One desperately wanted to make All Might suffer for everything that he’d done. But if he chased two birds, he’d catch neither. Returning to his full strength. Returning to his family. That was the priority. Once he was strong again, it would be easier to take care of All Might. He wouldn’t underestimate him again.

As it turned out, the quirk All for One was seeking had yet to exist. It had taken 3 years, but All for One’s informants in the Yakuza had found something promising. A girl with the power to rewind time. Not actually go back in time- that probably would have broken reality itself anyways. But undoing the passage of time on what she touched was more than enough.

While he planned on taking the child by force anyways, considering the conditions she was in All for One was certain he rescued her from far worse a fate. The Yakuza All for One remembered were at least honorable- they wouldn’t hurt their own. They wouldn’t have engaged in those kind of experiments with an innocent child. Not to say that All for One himself wouldn’t have done something similar. But well… His own new experience as a father made him more reluctant to intentionally harm a child.

When All for One found Eri, it was a simple matter of earning her trust. Being a person’s savior from those that hurt them certainly helped. It worked like a charm with Shigaraki, and while the girl’s recovery was a long ways off, she at least trusted her new Sensei.

Of course, it couldn’t be as simple as her simply using her quirk on him. Before he could help her get better control over her quirk, he needed to help her get over that mental block of using it in the first place. That damned Chisaki had her thinking it was some kind of curse. Psychological manipulation like that was the only tool he had to keeping the girl from turning against him. It was far easier to control a child with positive reinforcement, but All for One supposed that was more difficult to manage while you were treating them like a lab rat.

He just needed to help her work toward a goal. Using her quirk to help people. To heal people like him. She needed to see a willing target. One that wasn’t afraid of her or her quirk. Nothing but praise as she turned a decades old tree back into a seed. Show no fear when she tested her quirk out on the unfortunate sap that went from a 40-year old man to a 5-year-old adolescent. And they were paid damn well enough to act just as happy to be alive in whatever state by the time they were done.

But this was good! After a few months of training with her, she was willing to use her quirk. The target was free of any injuries gathered over time, yet their memory was intact. She still couldn’t always control the amount of time that passed, but All for One had decades to spare. He was the perfect test subject for her.

All for One knew he was too eager to return to full health. To return to his family. But he was used to feeling invincible. He was eager to return to that again.

4 years. That’s all he needed her to rewind. And if she overshot, it should be fine. From the looks of the test subjects, it seemed painless. He could feel the years slipping away. The skin regrowing. His eyes… he could see again. It was like being pulled into a rushing tide. He didn’t want to fight the current.

His injuries. They were gone. But now his body felt like it was closing in on him. Like bleeding, except it was bone, skin and muscle being drained from him. Not good. He fought against the current trying to pull his way out. The fear of being rewound past his very existence tugged at him as he struggled against time itself.

All for One knew he should have gotten more test subjects. But he was losing valuable time he could be spending with his family when the solution was right in front of them. He should have realized the phenomenon the Yakuza were studying with Eri’s blood- to rewind the emergence of quirks itself. Rewind didn’t turn back the chronological time that had passed. It turned back the biological age. And while this distinction didn’t make a difference in many other subjects, for All for One who was biologically currently a man in his late 30’s, Eri’s quirk could have potentially turned him to dust like her father.

He supposed he should have counted himself lucky that he’d only been reduced to a teenager.

It was… a shock. He assured Eri that he was not upset with her, and that she had accomplished exactly what he hoped she would do- heal his injuries. Even if her main purpose was accomplished, she could still be useful. Best to continue to keep her happy and healthy.

The question was how to move forward. Literally. All for One had quirks to reverse his age, but he had no reason for one to advance it when that happened naturally. He had plenty of quirks to subtly change his appearance, but with his body like this he’d look like a kid no matter what he did.

He could go back to looking for the right quirk. This time one to advance his age- or at least his appearance so he could shapeshift the bone structure required to appear like an adult again.

On the other hand… this could be an interesting opportunity.

All for One always feared that Izuku and Inko would discover the truth about him and they’d hate him for his crimes. That he’d lead his enemies straight toward them.

But in this form… It was a blank slate. No one would think to look for All for One in the form of a teenage boy. And now, All for One appeared around the same age as his son. He could come into his life through a different route. Stay closer to him and keep him safe better than he could as his father.

From the reports All for One had received, Izuku was still dead set on becoming a hero, even quirkless. He could try and become someone he trusted. A friend that could see the world from his shoes, and possibly convince him of a more beneficial path for him. Doctor, politician, lawyer- anything that could put his head to better use than some kind of celebrity white knight.

Kurogiri would be his one link back to the criminal underground. He could keep watch over Shigaraki and his League, and should All for One absolutely need to step in, he could always use a quirk to change his voice. He already mostly just a voice on a screen to most of the criminal underground over the past few days anyways.

Kurogiri could care for Eri as well- he was the only one he trusted enough to leave her with. The last thing he needed was Tsubasa reopening her up as a human quirk suppressant factory. She could be far more useful to preserve what was precious to him. And as one of the few people that knew his new face... Well, it wouldn’t hurt to continue meeting with her and maintaining that bond.

A new identity was forged. All for One registered himself for Aldera Junior High.

Oddly enough, it didn’t feel belittling for the world’s most powerful supervillain to strut through the halls in a school uniform. It was actually a rather new experience for him. When his quirk emerged, in his day he was a mutant freak. When you were kicked out of your home, attending school wasn’t on his list of priorities so much as survival. It was somewhat refreshing to just be another face in the crowd. A wolf in sheep’s clothing mingling with the flock.

Classroom 2-B. He ensured he was in the same class as Izuku, otherwise this entire schooling would be pointless.

He stood before a sea of children who looked with mild curiosity at the new addition to their class a few months into the year. Putting on a practiced pleasant smile, he tried his best to make a decent first  impression.

“Introduce yourself.” The teacher impatiently asked. Ah, so she wasn’t going to give him any introductions? No transfer student spiel?

“Of course. You can call me Akatani Mikumo.” He needed to get used to this new name. But he’d slipped into plenty of different personas in the past before. He would set Hisashi Midoriya to rest for now. He’d learn to be Mikumo.

“My father’s job had me moving around in the past, but I’ve finally made accommodations to remain in-”

“We don’t need your life story.” The teacher snapped. “Just say your quirk and sit down.”

“My quirk?” Was that really how students introduced themselves today? “Are you sure you wouldn’t prefer my blood type? It’s just as useless of a way to tell everyone about myself.”

The teacher clearly didn’t appreciate the sarcasm. “If you’re so embarrassed about it, just take the empty seat in the back.”

Mikumo gazed across the class. The only seat open was in the far back corner. Three seats to the left and 2 behind his son. He could do better.

“If you see my file, I have specific seating requirements. I just need to trade with someone. Shouldn’t be too difficult.” It was easy enough to get the ear of the principle when your ‘father’ made a few donations.

Not that this incompetent excuse for an educator got the memo. “I’m not changing the entire seating arrangement because of some made up skin condition or whatever you’ve got. Take your seat and stop interrupting my class before we have a problem.”

So that was how it was going to be then? A minor inconvenience. He could dig up or plant something on this woman to get her fired. But Mikumo was supposed to be a normal teenager. Even if he left no evidence linking the incident if he had too many episodes of people being removed around him then it would be too suspicious. But if she continued to be a nuisance, he’d take care of it.

“Wouldn’t want there to be a problem.” Mikumo said flashing a honey sweet smile.

Mikumo paid little attention to the lecture. And from his observations, it seemed like neither did Izuku.

Even a few seats back, a telescopic vision quirk allowed him to easily look at Izuku’s notes, and it was far from middle school mathematics. Not the correct subject, but more advanced. Analysis on a hero by the name of Ricochet. Their quirk appeared to allow them to charge up small projectiles to infinitely bounce off surfaces until they canceled their quirk. Judging by how Izuku was scribbling down about angles and kinetic energy to try and discern the true nature of the quirk, it seemed like he was wasting his time in this class just as much as Mikumo was.

Mikumo drunk in every detail he could about Izuku. After a few years apart from him, he was desperate for whatever direct information he could get. The way he would seem to stare off into space before unleashing a herd of scribbles upon his notebook. How he ran his eraser down to ensure his notebook was kept pristine with all the important details. How he’d continue to flip back to older pages when he thought of any possible new details about how a quirk might be used. How easily he was able to snap out of his own world when the teacher decided to call on him. He did quite the decent job of dividing his attention enough to answer any of her questions.

Mikumo could hear a snicker from next to him.

“Got a crush on useless Deku or something?” It seemed like all his staring hadn’t gone unnoticed.

Deku- that was the nickname Katsuki had given Izuku, wasn’t it? Not a very kind interpretation of him. How badly was Izuku treated within the school walls?

“Rather rude to call someone useless, isn’t it?” Mikumo whispered back to the long-nosed student.

“Just stating the facts. Deku’s got no quirk. Just a heads up before you start bothering with him.”

How lovely. Just a taste of the Quirkless discrimination he was sure to observe in the coming years. He was aware of it- thrived on it in order to recruit new loyal employees. And it seemed like children were set on this meritless mindset early on. It wasn’t like the majority of them would be permitted to use their quirk in their daily life. And most quirks were only a minor modification. That’s where the name came from after all- just a small little oddities to make a person unique. Some had evolved from creating sparks to fireballs, but the majority of the population only had access to minor benefits. Yet lacking the ability to grow your hair twice as fast or make your nails glow? Clearly, how were you supposed to function as a human being without it?

It was probably hypocritical of him to think so with access to hundreds of different quirks, but there was really more you could do with a calculating mind than a powerful quirk. The longest living heroes relied more on their skills than their quirk. But it seemed like humanity was still willing to make a leper out of anyone with a genetic fluke. So much for valuing diversity in an era of green skin and pineapple heads.

“Thank you. Now I know not to bother with you then.”

That shut them up rather quickly. As class came to a close, Mikumo noted how Izuku quickly started getting his things together before the bell rang. Not so unexpected with half the class eager to get out for lunch as well, but it only meant he’d need to be quick to hunt him down.

Especially since he could already start seeing the other students turning his way. In a small school like this, a new student still at least seemed to be an interesting enough event to gain some people’s attention.

“Akatani, right?” A loud voice asked as their hand slammed down on his desk.

Already he was in the crosshairs of the blond haired red eyed menace that had been a nuisance in Hisashi’s home through Izuku’s early childhood.

Mikumo let out a sigh as he watched Izuku use Bakugo’s distraction to try and dart out the door. Well, he might as well get this over with.

“Yes, that’s what I said my name was.” Mikumo replied bored. “And you’re Bakugo Katsuki.”

The blond chuckled. “Some sort of mind reading quirk then?”

Mikumo shrugged. “Maybe. Or I can read the tag your mother left on your backpack.”

A few of the students crowding behind Bakugo snickered. He gave the one the nearest to him a shove.

“You think you’re so smart, why don’t you settle a bet? Tsubasa-kun here thinks your quirk is something embarrassing like your shit smells like roses. Me? I think you don’t have a quirk at all.” Bakugo launched.

There were a few gasps around him. Like he just accused the new kid of being sexually promiscuous. But All for One had endured worse taunts than the one from a school yard bully.

Mikumo looked Bakugo dead in the eye. “My quirk is Explosion.”

The shocked look on the blonde’s face was priceless. He really wished he could just take his quirk. If anyone deserved it, it was him. But that would be another incident that would bring attention to him.

Mikumo nodded and continued. “I’m a living nuclear reactor. If I get too annoyed, BOOM.” He said popping out his fingers like a firework.

“Liar! What’s it really?” Bakugo demanded as he reached out to grab Mikumo’s shirt collar.

Being behind a desk and surrounded limited his escape options without breaking out a quirk. But he could still work with this. He shoved the desk into Bakugo’s gut. A cheap light desk wouldn’t hurt him much, but it certainly stopped his assault.

“Academikinesis. I can control any sort of object or furniture you can find in a school setting.” Mikumo replied in a deadpan voice even as all the students began to back up. They knew how Bakugo could get right before he got ready for a fight.

“Hey! I saw him push that desk, he’s making it up!” Some braniac behind Bakugo noted.

“Of course he is you dolt!” Bakugo shouted guarding his stomach. He turned back to Mikumo who was simply casually grabbing his things like he hadn’t just thrown the hatchet. “Listen up you wise ass- I’m on top of this shitty school, and once I graduate I’m going to be #1 in the world!”

“Ah, world domination. Can’t dissuade you enough on it. Not worth the hassle. And while you seem to have the villain part down, I don’t think you have the management skills for it.”

“JUST SHUT UP!” Bakugo shouted as sparks began to flare up in his hand.

Mikumo’s eyes glimmered at the sight of the quirk use. It was a fairly powerful quirk. He probably could make it as a hero with that alone. And if he was so free to use it now, chances were it hadn’t gotten him in any trouble with adults in the past. Wouldn’t it be nice to watch him stare back in horror as Bakugo’s own quirk ignited within Mikumo’s palms? Maybe one day. But not without planning.

Mikumo abided by Bakugo’s wish, but not without a creepy smile. All for One had certainly masked the art of imposing fear with nothing but his body language. And even if it was trickier in a younger body, he could see by the way the students around him froze that it was still effective enough. No quirk required. Just little ways to trigger a person’s pure instincts.

“Creepy ass fuck.” Bakugo muttered trying to act uninterested as he backed away and left to get his own things.

“Oh? No challenge to meet me at 3 out behind the school?” Mikumo asked with a chuckle. “And I just needed one more hit before I filled out my bully bingo card.”

“You better watch your back.” Bakugo yelled as he refused to look Mikumo in the eye or let him have the last word before walking off.

The other students still remained looking in awe. Plenty of people tried standing up to Bakugo, but none could really match him. Not that any could blame him. They agreed- new kid was ‘creepy as fuck’ as Bakugo noted.

“Is that your quirk?” A nervous voice asked from the classroom door.

Izuku… apparently the commotion had him curious enough to return. Ah… he hadn’t meant for him to see that. Not the kind of first impression he wanted to induce.

Mikumo had half a mind to lie. Some kind of intimidation quirk was an easier pill to swallow. But half the point of him being here was to keep Izuku safe. He was going to see something like that eventually.

“No.” Mikumo quietly answered letting the overconfidence and offsetting aura fade. “But picking the face you put on… it can stop a battle before it has to escalate.”

Acting and melodrama- it wasn’t just for creating dramatic speeches right before the hero’s doom. It was a mask useful for any situation.

Izuku seemed to ease up a bit at hearing that. “Just like All Might.”

Mikumo had to grit his teeth to prevent himself from showing any kind of reaction. Compared to his arch-enemy. Izuku accidentally managed to create a crack in his perfectly constructed mask.

But no one seemed to have noticed. “Excuse me?”

“All Might’s smile… With that alone, he can convince villains to surrender. It’s not just for bringing hope- it makes villains realize they don’t stand a chance!” Izuku’s smile was bright as he talked about his favorite hero.

Mikumo eased up. He couldn’t be cringing every time he heard All Might’s name, and Izuku only meant well by it. “I guess I should be flattered by the compliment then.”

“If you can stand up to someone like Bakugo… I’m sure you’ll make a great hero!” Izuku beamed.

Mikumo almost felt guilty for a moment. Did he even realize what he was saying? Who he was talking to? No, of course not. “Who said I wanted to be a hero?”

Izuku blinked confused. “Oh… I just assumed… I mean, just about everyone wants to be a hero… Sorry! What do you want to be then?”

It was always so easy to fluster Izuku. Part of him was relieved that his son hadn’t changed much in his absence. That he still had a chance to watch him grow. Even if he couldn’t be his father, he could still be in his life.

“Oh, whatever I want to be I suppose.” He answered nonchalantly. “How about I start with, your friend?”