Three Days Later
The Musutafu Community Dojo was a modest building tucked between a convenience store and a small restaurant. Its wooden sign had faded with age, and the windows showed a simple training floor with padded mats. Nothing fancy, nothing flashy—exactly what Inko had been looking for.
Inside, a stern-looking man in his fifties watched as students practiced basic katas. His name was Tanaka Kenji, a former pro hero whose quirk—minor density manipulation—had never been powerful enough for the top ranks, but had made him an exceptional martial artist. After an injury ended his hero career, he'd opened this dojo to teach practical self-defense.
"Midoriya-san?" He approached as Inko entered with both boys. "You called about enrolling your sons?"
"Yes, thank you for meeting with us." Inko bowed respectfully. "This is Kaito, he's nine. And this is Izuku, he's four."
Tanaka's eyebrows rose as he looked at Izuku. "Four is quite young to begin serious martial arts training."
"I can do it!" Izuku said quickly, his voice determined. "I'll work really hard, I promise!"
Something in the boy's intensity made Tanaka pause. He'd seen that look before—the desperate need to prove oneself. "And you, young man?" He turned to Kaito. "Your mother mentioned you already have significant physical capabilities."
Kaito nodded. "Yes, sir. But I want to learn proper technique. And I want to train with my brother."
"Hmm." Tanaka crossed his arms, studying both boys. There was something unusual here—the older boy's protective stance, the younger one's fierce determination despite his small size. "Tell me, Izuku. Why do you want to learn to fight?"
Izuku clutched his hero analysis notebook tighter. "Because... because I'm going to be a hero, sir. And I need to be strong."
"Your quirk?"
The silence stretched for a moment before Izuku answered quietly, "I don't have one, sir."
Tanaka's expression didn't change, which somehow made it better than pity would have been. "I see. And you?" He looked at Kaito.
"I want to be a hero too," Kaito said. "And I want to make sure my brother can stand beside me when we do."
Tanaka was quiet for a long moment, then nodded sharply. "Very well. But I have conditions. First, this will not be easy. Izuku, you will be training with students twice your age. You will be pushed to your limits. There will be days you want to quit."
"I won't quit," Izuku said immediately.
"Second," Tanaka continued, looking at Kaito, "you will suppress your quirk during all training sessions. No enhanced strength, no invulnerability. You will train as if you were a normal human. Can you do that?"
Kaito's face became serious. "Yes, sir. I can hold back my strength. My durability... that's harder to turn off, but I'll take hits like they hurt, and I'll tap out if I would be injured."
"That will do." Tanaka gestured to the mats. "Then let's see what we're working with. Both of you, basic stance."
Two Hours Later
Izuku's legs were shaking, sweat pouring down his face as he held the horse stance for what felt like the hundredth time. Every muscle in his small body screamed in protest. Around him, older students moved through their forms with practiced ease, but Izuku refused to look at them. His eyes stayed fixed on Kaito, who was in the same stance beside him, also trembling with effort despite his superior strength.
"Keep your back straight, Izuku," Tanaka's voice called out. "Don't let your knees cave inward. Good, Kaito—remember, you're training as if you were normal. Feel the burn."
"Feeling it, sensei," Kaito grunted, and despite the pain, Izuku almost smiled. His brother could lift a car over his head, but he was suffering through the same basic exercises, never once complaining or using his powers to make it easier.
"Time!" Tanaka finally called, and both boys collapsed to the mats, breathing hard.
"That was just the warm-up," Tanaka said, and Izuku's eyes widened in horror. "Five minute break. Drink water."
As they sat against the wall, sharing a water bottle, an older student—maybe twelve or thirteen—walked over. He had spiky brown hair and a confident smirk.
"You're the Midoriya brothers, right? I've heard about you." He looked at Kaito with obvious interest. "They say you're crazy strong. That you can fly and shoot lasers from your eyes."
"Heat vision," Kaito corrected mildly. "Not lasers. And yeah, I guess."
"Cool." Then the boy looked at Izuku, and his expression became skeptical. "And you're the quirkless kid who thinks he can be a hero?"
Izuku's hands clenched, but before he could respond, Kaito's hand rested on his shoulder.
"He doesn't think," Kaito said calmly. "He knows. Just like I know I'm going to be right there beside him."
The older boy shrugged. "Whatever. Just seems like a waste of time to me. No offense, kid, but maybe you should aim for something more realistic."
After he walked away, Izuku stared at his small hands. "Maybe he's right, Kai. Maybe I'm being stupid—"
"Stop." Kaito's voice was firm. "Don't let anyone else define what you can or can't do. You know what I see when I look at you, Izu?"
"What?"
"I see someone who's been told he can't achieve his dream, and instead of giving up, he's here. At four years old, putting himself through physical hell because he's determined to make it work." Kaito smiled. "That's not stupid, little brother. That's heroic."
Before Izuku could respond, Tanaka called them back to the mats.
The Next Two Hours
If the warm-up had been hard, the actual training was brutal. Tanaka put them through basic falling techniques, teaching them how to roll and break their falls properly. Izuku hit the mat over and over, his small body bouncing awkwardly until he started to get the hang of it.
"Tuck your chin! Roll through the shoulder!" Tanaka's instructions were constant. "Again! You're going to do this until it's instinct!"
Then came basic blocking drills. Tanaka demonstrated how to deflect strikes, how to position their bodies to minimize impact. For Kaito, who'd never actually needed to block anything in his life, it was surprisingly difficult. For Izuku, whose arms ached with every movement, it was agony.
"Pair up!" Tanaka called. "Older students, you're helping the younger ones. Kaito, Izuku, you're together."
They faced each other on the mats, and Kaito threw a slow, gentle punch toward Izuku's face. Izuku tried to block like Tanaka had shown, but his timing was off and the punch—even at minimal force—tapped his cheek.
"Again," Kaito said patiently.
They repeated the drill dozens of times. Slowly, Izuku started to get it—the timing, the angle, the slight redirection rather than stopping the force completely.
"Good!" Tanaka appeared beside them. "Izuku, you're learning fast. Your body awareness is developing well for your age." He looked at Kaito. "And you're an excellent training partner. Patient, controlled. That's rare."
Kaito grinned. "He's my brother, sensei. Of course I'm patient with him."
End of Class
By the time Inko arrived to pick them up, Izuku could barely walk. His legs felt like jelly, his arms hung limp at his sides, and he was pretty sure every muscle in his body had filed a formal complaint.
Kaito looked tired too, but he still scooped Izuku up and carried him to the car.
"How was it?" Inko asked, concern evident in her voice as she saw Izuku's exhausted state.
"It was amazing, Mama!" Izuku said, his voice hoarse but excited. "Sensei Tanaka said I'm learning fast! And Kai helped me with all the blocks, and I only cried twice when I fell wrong, and—"
"You cried?" Inko's eyes widened.
"Happy tears!" Izuku insisted. "Because I did it, Mama. I actually did a real hero training class!"
Kaito settled into the back seat beside his brother. "He was incredible, Mama. Sensei Tanaka said most kids his age would have quit after the warm-up, but Izuku kept going for the full three hours."
"Three hours?!" Inko nearly swerved the car. "Izuku, honey, that's too much for someone your age—"
"No it's not!" Izuku protested. "I can do it! I have to do it! If I'm going to be a hero without a quirk, I need to train harder than everyone else, starting now!"
Inko glanced in the rearview mirror at her youngest son, seeing the fire in his eyes that no amount of exhaustion could dim, and felt her heart break and swell at the same time.
That Night
Izuku lay in bed, unable to move without wincing. Every part of his body hurt. It was the best he'd felt in months.
"Kai?" he whispered into the darkness.
"Yeah, Izu?"
"I'm really sore."
Kaito chuckled softly. "Me too, actually. Sensei Tanaka doesn't go easy on anyone."
"Do you think... do you think All Might trained like this when he was little?"
"Probably even harder," Kaito said. "All the great heroes did. That's what separates them from everyone else—they push past the pain, past the doubt, past what everyone says is possible."
Izuku was quiet for a moment, then said softly, "Kai, what if I'm not strong enough? What if no matter how hard I train, it's not enough because I don't have a quirk?"
Kaito sat up and moved to Izuku's bed, sitting on the edge. Even in the darkness, his presence was comforting.
"You want to know something about strength, Izu? Real strength isn't about how much you can lift or how powerful your quirk is. It's about how many times you can get knocked down and still stand back up. It's about facing a world that tells you you're not good enough and saying 'watch me prove you wrong.'"
He ruffled Izuku's hair gently. "You've got that strength, little brother. I see it every single day. And yeah, the road ahead is going to be hard. Really hard. But you're not walking it alone. You've got me, you've got Mama, and you've got your own unbreakable will."
"You really think I can make it to UA?"
"I don't think, Izuku. I know." Kaito's voice was absolutely certain. "In ten years, we're both going to walk through those gates together. The Midoriya brothers. And we're going to show everyone what real heroes look like."
Izuku felt tears prickling his eyes—good tears this time. "Thanks, Kai."
"Always, little brother. Now get some sleep. Tomorrow we train again."
"Tomorrow?!"
Kaito laughed. "What, you thought we were stopping? Heroes train every day, Izu. Every. Single. Day."
Despite his aching muscles, despite the long road ahead, despite everything the world said about quirkless kids and impossible dreams, Izuku Midoriya smiled in the darkness.
He was four years old, he couldn't even do a proper push-up yet, and his body felt like it had been run over by a truck.
But he'd taken his first real step toward being a hero.
And with his brother beside him, he knew he could take a million more.