Chapter Text
Genetics is a very tricky subject.
The Doctor knows it; that’s exactly why he adores it so much. A single human genome held an intoxicating number of variables—countless microscopic forks in the road where a life was built or broken.
Mutations are architect to the design of a biological masterpiece. Much like the threads of destiny, they dictate from birth what your life will be. What a graceful ballerina you could become with just the right genes to transmit information between nerve cells! So sad it’s not the case… Or maybe you could end up being an unfortunate soul who will spend their entire life in a hospital because of it.
Potential lies entirely in predispositions. Working hard will help you perform, sure, but not achieve perfection. Passion cannot overcome the raw talent given by blood and sequences. Some people are simply born to be better. Let’s say you see a picture of a sunset and an aurora borealis. Which one would you like more? The first is ordinary, it’s pretty but you see it every day. The latter, however, is unique. It makes people travel countries and leaves them gaping in awe.
Genetics decide who becomes a sunset and an aurora.
It creates a winner and a loser, which picture gets picked.
As bleak as it might seem, the Doctor believed it was the truth behind the shining miracle of humans. But the scientist knew everyone had a use, a path their body had created for them.
He was designed for science! Learning! He also had an eye for potential. When All for One approached him a century ago, he saw excellence. His quirk was perfection incarnate, and it gave his miserable life a goal: he needed to live to serve and to help him. He would make whatever sacrifices were necessary. Besides, who would suspect kind, quirkless, award-winning genetician Garaki of stealing bodies from the hospital morgue? Leaving such tissue in pristine condition and genetic material to rot in an incinerator was a criminal waste, especially now that the new project, “NOMU,” was underway.
A light knock rattled the frosted glass of his office door.
A riffle of green curls entered his small office, followed by a slim woman with a low bun the same color as her son’s hair and a clinical nurse. His staff member smiled at him and she extended her hand to give him a file before exiting the room.
Shit.
Right, he had an appointment. Keep the cover-up to please the boss, Garaki.
He shuffled a couple of papers on his desk to remember which case he was dealing with.
Midoriya Izuku. Age four.
Speaking of quirks…
Two days ago, a single glance at the boy’s foot X-rays had told the entire story: two distinct joints in the pinky toe. The child was Quirkless. Garaki had done a genuine double take when the radiograph came across his desk. With every passing generation, finding a Quirkless child was becoming an anomaly. In a family where both mother and father possessed functional Quirks, it was practically a statistical impossibility.
“Mrs. Midoriya, right? Come in, come in. Hi buddy, we have a lot to discuss today. Please take a seat, we have a few things to go over today. Feel free to take a cookie from the jar, my son brought me a box yesterday. ”
The doctor put on a slightly saddened expression, looking like a professional who cared deeply for his patients. In truth, he didn't dislike children : he just preferred their cold bodies on an operating table.
It was more useful that way.
And quieter.
“Is he… is he just a late bloomer, Doctor? My baby should have shown signs by now. All his classmates at preschool already have their Quirks, and Izuku is… he's starting to feel left behind. I just can't bear seeing him… so sad,” muttered Inko, on the verge of tears.
The child sat beside her, far quieter than his mother. He was gripping the hem of his oversized orange T-shirt with one small hand while furiously scribbling in a spiral notebook with the other. Scratch, scratch—pause—scratch. A repetitive, nervous rhythm.
Garaki rested his hands on the desk and folded them over the file.
“I’m afraid he’s not a late bloomer, Mrs. Midoriya.”
He was quiet for a moment, letting the mother and son take in the news.
The frantic scratching of the pen in the kid's hand stopped dead. A low, strangled sob laced with a gasp escaped Inko’s throat. The little notebook slipped from the boy’s numb fingers and hit the floor with a hollow slap.
The doctor watched despair flood those small, beady green eyes.
How pathetic. Gosh, he was glad to have only one grandchild.
Those vermin were so dramatic.
“Based on his X-rays and currently available research, your son will not develop a quirk. Your son is quirkless. His skeletal development shows the vestigial joint. You'll want to buy footwear designed with that extra joint in mind. ProTech makes good ones, but really any red shoes will keep him comfortable. It’s an adjustment, certainly, but it won't impact his day-to-day health. This is a lot to hear. I understand.”
“Oh, Izuku… Baby, I’m sorry, I'm so, so sorry…,” sobbed the mother again while hugging her little boy.
The child didn't cry. He simply went rigid in her arms, his small hands hanging limp at his sides as if his entire world had just dissolved beneath his feet.
The sight might have melted his heart when he was younger, but he now felt bored watching them. Such a display of affection was repulsive and tacky. He picked up the notebook off the tiles on the floor out of politeness and absentmindedly peeked inside. While he was expecting childish drawings and stories, he was met with a scarily accurate description of the quirk of one of the nurses who led them inside his office.
“Yatanabe Chihana: Nurse
Quirk: Increase (supposition)
Type: Emitter
Observation : In the waiting room, she used her ability on herself twice. She put a man double her size on a stretcher, but she possesses a very frail body. She did not even react to his weight while lifting him—no signs of an obvious mutation quirk. A faint light could be observed on her body, which means she used her quirk on herself, not him, to help her with strength. If her quirk had been able to decrease the weight of the patient, the light would have been around him. Possibly super strength, but she showed signs of clumsiness while carrying the patient, leading me to think she was not used to doing that (the strength felt awkward to her?). Also used her ability while on the computer (light from before was observed), so it's not related to muscles.
Weakness: Not used to switching the abilities she increases, seemed to be sweating a lot during use (probably burns a lot of calories), poor general condition
Solution: Increased physical training, snacks to compensate
Strength: Versatile, ability is very easy to conceal
Garaki's eyes scanned the text once, then twice.
He flipped back a few pages. The notebook was filled with meticulous, layered analyses of Pro Heroes: structural weaknesses, biological limits, combat habits, reaction times, and tactical blind spots, all supported by equations and poorly drawn sketches.
A cold, venomous thrill sparked behind Garaki’s thick lenses.
Fascinating.
Here was no ordinary child. Here was an analytical prodigy—a raw, strategic intellect trapped in the weak body of a child. A Quirkless mind capable of dissecting the supernatural with terrifying accuracy.
Garaki hid his widening grin behind a somber, sympathetic mask. He had just stumbled across an invaluable piece for the board. The boy was a diamond in the rough, an asset that All For One could mold into a lethal analyst and the perfect right hand for young Tomura Shigaraki. All the boy needed was the right nudge, the right patron, and the slow crumble of his faith in society.
"Quirkless doesn’t mean useless, Mrs. Midoriya. I am myself quirkless, you know, and I am a respected doctor. People have the bad habit of often assuming quirkless individuals are weaker or dumber, but that’s just prejudice. You can achieve anything you desire if you put your mind to it. DNA is an instruction set, but your mind is your own." The doctor said in a sweet, understanding voice.
So what if he lied a little about his quirk status? Garaki knew how desperate people operated. Give them a villain, society’s prejudice, and they would take any hand extended to them.
All he needs is people to believe in him. Desperate kids will cling to any hope they can find, just like Tomura did.
"D-Does that mean I can become a hero even without a quirk?" the child hiccuped quietly.
"Izuku, honey, please don't trouble the doctor," Inko murmured, her eyes red-rimmed and anxious.
Garaki held up a gentle hand.
"Of course you can become a hero without a quirk, Izuku. But you must be practical about it."
Garaki opened a desk drawer, retrieved a printed brochure, and slid it across the wood toward Inko. The bold header read: All Fight Origin Academy: Muay Thai, Judo, and Practical Self-Defense for All Ages. Izuku’s gaze lit up, sparkling like an emerald basking in the sun.
"A Quirk is just a tool," Garaki said smoothly. "If you do not possess one, you must build your own tools through discipline and training. If you truly wish to protect people, you cannot rely on dreams alone. You must learn how to fight, how to read opponents, and how to survive."
Inko looked at the glossy paper, her cheeks flushing with embarrassed hesitation.The child also read it, more hope and happiness bleeding on his features.
"Doctor, this is… it's so kind of you, but we really can't afford a private academy like this. My husband works overseas, and our budget is—"
"Oh please, I insist! Think nothing of it," Garaki interrupted with an easy wave of his hand. "The head instructor is an old acquaintance of mine. I will speak to him personally, and my clinic will sponsor the boy's tuition and equipment. Consider it an investment in a bright young mind. When you arrive, simply tell them Dr. Garaki sent you."
" Please, mommy, can I at least try? I promise I will work hard! I will work twice as hard as anyone! "
Izuku was squeezing his mother's hand while giving her a pleading look with his round green eyes full of hope. Inko looked from her son's pleading expression to the doctor's kindly smile. She didn’t stand a chance. Overwhelmed with relief and gratitude, she bowed her head repeatedly, tears spilling over her cheeks once more.
How emotional could this women be ?
She sighed and gave a meek smile while nodding. She grabbed her son and put him in her arms, then headed toward the door.
"Thank you… Thank you so much, Dr. Garaki," she whispered, her voice thick with emotion. "You have such a generous man. We will go there this very afternoon."
"I'm going to be a hero!" Izuku declared, clutching the brochure to his chest like a most prized hero card. "Just like All Might! I'm going to do great things!"
"I have no doubt you will, little Izuku, I will see you at your next checkup."
As soon as the door clicked shut, the doctor's smile turned razor-sharp.
By two o'clock, Garaki had placed an encrypted call to his master, detailing the boy's uncanny intelligence and laying out a plan to begin private weekend tutoring in Quirk genetics and human anatomy.
By three o'clock, Izuku Midoriya was officially registered on the academy’s beginner roster.
***
"Harder! Put your hips into the strike!"
The dojo coach paced the edge of the blue tatami mats, his voice echoing off the high, mirrored walls.
"Keep your guard angled at forty-five degrees! Protect your chin and drive through the target! Amano, tuck your elbows in! Seki, stop hesitating—look for the hole in his defense, nothing is ever impenetrable! Exactly like that, Midoriya!"
An nine-year-old Izuku slipped under an incoming swig, pivoted on his lead foot, and drove his knee to strike into his opponent’s padded ribs. Without breaking momentum, he followed the blow with a quick one-two punch combination, forcing his partner backward onto his heels. Izuku stayed low, his center of gravity rock-solid. His eyes were locked on the older boy's shoulders.
His opponent patiently waited for Izuku's weight to shift forward, and swept his back leg in a low vicious arc.
THUD!
Izuku’s footing completely vanished. He hit the mat hard, the breath knocked out of his lungs with a sharp grunt. He stared at the ceiling fan spinning over his head as the shock of the impact rattled through his spine.
"Point," the coach barked from across the room.
Yukio Sato stood above him, panting lightly. Two years older and nearly a foot taller, the blond boy brushed a stray lock of sweat-dampened hair out of his eyes, his ponytail swinging over his shoulder. He grinned down at Izuku and offered an open hand.
“Outch.. that really hurt,” Izuku mumbled, rubbing the back of his neck as he took Sato’s hand and let himself be hauled up. “That sweep was amazing, Sato-san! It completely caught me off guard. You have to show me how you set that footwork up.”
"You're the one who almost cracked my ribs, Midoriya-kun," Sato laughed, wiping sweat from his forehead with the back of his forearm. "Your striking is way sharper than last month. But you still get tunnel vision once you land a good combo. That’s your big problem. You stopped watching my lower body."
"I thought I had you off balance—"
"You did, but I knew you'd push the advantage," Sato said, clapping him on the shoulder. "Trust your instincts more, man ! You already read people faster than anyone else here. Give it another year or two and you'll be the one sweeping me across the room."
Izuku immediately shook his head to protest, but was interrupted by the coach's overenthusiastic, loud voice echoing through the gym. The chatter and laughter immediately died down as the children respectfully put their hands behind their backs.
“OK, people, that's all for today's lesson! Make sure you have everything before you leave because I'm sick of y'all forgetting your water bottles here and playing ``Guess who`` with them. Next week we move into advanced judo throws, and the after-hours group is starting boxing fundamentals. Hope you all had a great day !”
The students answered with a chorus of ``Thank you, sensei!” and multiple bows all at once. Izuku bowed deeply, gathered his towel and gym bag, and made a beeline for the locker room.
Old habits died hard.
Years of bullying had made him an expert at his quick changes more than he liked. Even here, in a dojo where the other kids treated him with respect, he felt a knot of dread in his stomach whenever adults weren't in the room. He half-expected a shoulder check into the metal lockers, an insult, or someone tossing his clothes into the shower stalls.
He knew he could defend himself, but he hated the thought of hurting someone for something so insignificant. His mother told him when he started martial arts to “Only use his strength as a last resort”. A broken nose didn’t fix equally, it only bred deeper, uglier resentment.
"Hey man ! " Sato called out from down the bench, unlacing his hand wraps. "You always pack up like you're running from a fire. Your mom that strict about curfew?"
"Oh, no, no she's great!" Izuku replied, forcing a bright, easy smile as he zipped his duffel bag. "She just worries if I'm even five minutes late, so I try to beat her texts."
After a quick shower and a change into clean street clothes, Izuku pushed through the dojo’s glass front doors. August heatwave had been persistently knocking on Tokyo’s door for a week, which led Izuku to wait outside the dojo in the shade instead of the scorching sun near the exposed curb. He already missed the AC inside and just prayed his mother wouldn't run late.
He pulled out his phone. Inko had responded to his "Are you close?" text with a single frustratingly random emoji (which usually meant she had gotten distracted at the work and was running fifteen minutes behind).
Izuku sighed, letting his shoulders slump against the cool brick wall.
Beside him, sitting criss-cross on the ground, was a kid he had never seen before in lessons hunched over a gaming console. He looked slightly older—maybe ten or eleven—with unruly, pale blue hair that fell over his face and pale, chapped skin. He hadn’t even bothered to turn off the sound, and the clanking of swords was on full blast.
“Stupid game, garbage.”
Izuku glanced at the screen and recognized the dungeon almost immediately. He remembered the constant whine and frustration cry of Sato as they cleared it a few weeks ago. He wasn’t a big fanatic of video games, but he it didn’t mean he hated it. He enjoyed hero-based game and RPG, he certainly wouldn’t turn down the offer to play from his friends.
"Um…" Izuku started, taking a hesitant step closer.
“What?”
“Y-Your game…”
Izuku timidly pointed, god that kid was intimidating by his tone alone. You can do this Izuku, don’t give up now !
“You need a full party for that dungeon. I don’t think it’s possible alone.”
The older boy didn’t even look up, he acted as if he was an annoying fly disturbing his sleep. Troublesome but insignificant.
“I don’t need a party.”
“…But that boss has an unblockable critical attack at 20 percent health.”
“I’ll dodge it.”
“And the second phase has an area-of-effect burn that covers the whole floor”
“I’ll beat it before then.”
Izuku scratched his freckled cheek and sat down on the concrete a few feet away, keeping a polite distance. Something in him reminded Izuku of Katchan before he found out he didn’t have a quirk. Maybe he just missed his best friend and looked for him in every soul he came across. It didn’t matter anyway.
“…That’s really hard.”
“So?”
“So…” He scratched his freckles cheek. “Wouldn’t it be easier with a healer or another support ?”
“I don’t need someone babysitting me. I can do that myself just fine. ”
“They wouldn’t be babysitting you, they would be helping you ! That’s completely different. They keep you alive so you can do your damage. That's not dragging you down, that's making sure you actually win.”
“They’d slow me down, ok ? Christ you’re annoying...”
Izuku watched as the boss slammed his knight across the arena for what must have been the sixth time in a row. His EXP bar dropped before the screen flashed the mocking crimson letters : YOU DIED!
“…It doesn’t look like you’re going faster to me.” Izuku accidentally let out.
The older boy finally looked up and shot him a glare.
His face was flushed with embarrassment and rage. Beneath his pale blue hair, dark, bruised circles hung under piercing ruby eyes. His dry lips were pulled back in a sharp scowl, his fingers digging into the plastic shell of the console until his knuckles turned white.
"Sorry," Izuku said quickly, raising his hands in a placating gesture. "I didn't mean to make fun of you."
A few quiet seconds passed before Izuku dared to spoke again. Izuku didn't look away, but he kept his posture relaxed and open. Growing up under the shadow of explosive tempers had taught him how to read agitation. Some people were hot headed by nature, he supposed his quirk fell into the destructive category for him to act that way. He would ask Garaki for information about that in their next lesson on Tuesday.
“I usually play healer.”
“…Seriously?”
There was a trace of excitement among the disbelief that the green haired child didn’t miss. Izuku nodded enthusiastically and frantically searched in his bag for a pen.
“I like watching everyone’s health bars go up. It’s fun trying to keep everyone alive and lead them to victory ! That way I’m helping in my own way.It feels like… like I'm contributing to the victory, even if I'm not the one landing the final blow.”
“That sounds so boring wow. Thank you for that input. You’re doing all the work while everyone else gets the glory ? You don’t even know if they’re gonna protect you back. ”
“Good healers don't just stand there waiting to be saved, they can do a lot ! But even if they don't get the glory… the dungeon still gets cleared, right?"
The boy stared at him, his ruby eyes narrowing as if trying to solve a puzzle that didn't make sense.
“…Why would you want to do that?"
Izuku blinked, genuinely confused by the question. To him, the logic was as natural as breathing.
"Because heroes don't save the world alone," Izuku said simply. "They need a team."
The older boy went still. He looked down at the console in his hands, where the game had reset to the dungeon entrance.
"…Stupid logic," he muttered, though there was no bite left in it.
He tapped the button to restart the raid, charged into the first room and died within thirty seconds.
“…Whatever.”
He tried and died again.
“…”
Without saying another word, he scooted the console a few inches toward Izuku.
“…Fine. What’s your tag ? ” Izuku’s face lit up.
“Really ? Wait, let me write my player ID, we can play together after dinner if you want ! I just have to ask my mom to use the computer. Im Izuku by the way, Izuku Midoriya !”
He handed the scrap of paper over. The older boy took it, glancing at the tidy handwriting before stuffing it into his dark hoodie pocket.
"Tomura," he muttered, his dry lips twitching into the faintest hint of a smirk. "Tomura Shigaraki. Don't make me carry you."
***
All For One listened to the audio crackle through his earpiece: Tomura Shigaraki. Don't make me carry you.
A slow, delighted smile spread across the mastermind's face.
"Splendid work, Doctor," All For One murmured into the quiet room.
"Its time to move forward with the plan. I think we waited long enough. "