School had just let out, and Kaelen walked the familiar streets back home. The late afternoon sun painted the city in soft gold, shadows stretching long across the pavement.
He felt a strange sense of comfort in knowing he still had his memories—otherwise, navigating this strange life would have been impossible.
Reaching his home, he fished out the key from his pocket and unlocked the door. The interior was plain but neat, the quiet hum of an empty house settling around him.
His parents weren't home; both were away on a business trip. Kaelen, an only child, found himself alone in the world he now occupied—a strange mix of relief washing over him.
He walked up the stairs to his room and collapsed onto the bed, staring at the ceiling. Thoughts swirled in his mind.
'I want to be a hero, that's for sure,' he thought, letting his fingers drum on the sheets. 'To do that, I'll have to get into U.A. It's not easy… but not impossible either. One thing's certain: I need to understand my quirk.'
He rolled off the bed and planted his feet firmly on the floor, fists clenching almost instinctively. With a sharp inhale, he threw a punch.
At first, it was a simple strike—nothing extraordinary. Then, without a pause, he followed through with another punch from the same arm. It moved faster, harder, and struck with a weight that surprised even him.
It was as if the first strike had propelled the second forward, amplifying its force.
Kaelen grinned as he began experimenting, realizing the full scope of what he could do. His quirk wasn't just his fists; every movement mattered.
Every step, every swing, every pivot, every leap—each action stored energy in his body. Plus the longer he stayed in motion, the faster, stronger, and more devastating his attacks became. A jab, repeated, could snowball into a strike capable of sending an opponent flying across a room.
He paused for a moment, flexing his fingers and feeling the latent energy thrumming beneath his skin.
'The things I could do with this quirk…' he murmured, a smirk tugging at the corner of his mouth. 'I'm not just a kid in a strange world. I'm something else now.'
The room seemed smaller suddenly, the walls closing in with the energy he could barely contain.
He clenched his fists again, bouncing lightly on the balls of his feet, imagining what it would feel like to take this energy out into the world.
'U.A. won't know what hit them.'
Kaelen peeled off his uniform and decided to test the limits of his quirk. Standing in his underwear, he clenched his fists and began a barrage of punches. The first strike was simple, controlled, almost lazy—but by the fifth, he could hear the wind whistling past his fists as they cut through the air. A grin spread across his face.
'I guess I can get to five… let's see where I stop,' he thought, pushing further.
Momentum built like a wave. By the seventh punch, a sharp burning sensation shot through his arm, hotter than it should have been. He froze mid-motion. Staring at his limbs, he realized the muscles felt torn, strained, every fiber screaming in protest. Cramping pain shot up his forearms.
"God… this hurts," he muttered, slumping his arms onto his thighs, unable to lift them.
He sank onto the edge of his bed, waiting for the pain to fade. When the burning finally eased, he flexed his hands experimentally, feeling the tingling return to normal.
'This quirk… it's pretty overpowered. And it's not just attacks—just moving faster builds energy too. Good thing it only works when I want it to, otherwise I'd shred my muscles just walking to the bathroom,' he thought, a wry smile tugging at his lips.
Kaelen rose and headed to the bathroom, filling the tub while perching on the toilet seat. His mind wandered as he waited for the water to warm.
'I mean, boxers punch insanely fast because of years of training. I can do the same—develop my muscles, condition my body. I'm only 13… and in ten months, Izuku's going to meet All Might. I've got plenty of time to get ready for U.A.'
He flexed his fingers, imagining the attacks he could chain together once his body caught up to his quirk. Every thought made his pulse quicken—not with fear, but with excitement.
'I'm going to make this work. I have to.'
Afterward, Kaelen slipped into the bathtub, letting the warm water soak into his aching muscles. He leaned back against the porcelain, sighing in relief as the dull throb in his arms slowly melted away. Even though he was a die-hard anime fan, he wasn't the type to slack on personal hygiene. He liked to stay sharp, clean, and presentable—after all, heroes weren't just strong, they were symbols.
Once he finished washing, he dried off and returned to his room. Pulling on some casual clothes, he settled into the chair at his desk. The glow of his computer screen lit the dim room as he pulled out a notebook and pen.
He began writing.
A rough list at first: training goals, physical conditioning, quirk control, stamina. Then he opened browser tabs, searching up martial arts techniques. Boxing, karate, taekwondo, muay thai—even judo grips and movement drills. He skimmed articles and videos, carefully jotting down notes.
'Just throwing random punches won't get me anywhere. If I'm gonna build momentum, I need form. Technique. A real foundation,' he thought, tapping the pen against the desk. 'Plus, let's be honest—it'll look cool as hell.'
He smirked, flipping to a clean page in his notebook. At the top, he wrote in bold letters: Momentum Training Journal.
This wasn't just a plan. It was a promise to himself. Every discovery, every improvement, every mistake—he would record them all. That way, he'd never repeat the same errors again.
For the first time since waking up in this strange new life, Kaelen felt grounded. Focused.
'U.A., heroes, villains… whatever comes my way, I'll be ready.'
With that thought, he leaned back in his chair, the faint buzz of determination burning in his chest.
He pulled out his textbooks from his school bag and stacked them neatly on the desk, their weight thudding against the wood. The pages smelled faintly of ink and paper, reminding him of just how long he'd been away from actual studying in favor of… other thoughts. Even with the knowledge he had inherited from his predecessor, there were still gaps—huge, yawning ones—that couldn't be filled with memory alone. If he was going to thrive in this world, he couldn't afford to be careless with the basics. Knowledge, both of this world and his own, was a weapon.
He flipped open his math book and grimaced at the sea of numbers, formulas, and problems waiting for him. His pencil tapped against the desk as he muttered,
"Quadratic equations again… seriously? Out of all the things I had to redo in life, why math?" He leaned back, sighing in exaggerated despair, before bending over again and scribbling out solutions.
Slow, deliberate. Even if it wasn't fun, he knew this discipline mattered. Passing school was as important as training his body—both parts of his cover, both things his future needed.
By the time the clock ticked later into the night, Kaelen's notes were covered in messy but determined handwriting, doodles in the corners betraying how often his mind wandered.
Still, he persisted, closing the books with a small sense of accomplishment. "Alright," he muttered, stretching, "that's one less thing to worry about."
---
The next morning, his alarm buzzed sharp and relentless at 5:00 AM. Kaelen groaned but forced himself out of bed, rubbing the sleep from his eyes.
The air was still cool, the sun not fully up yet, and the neighborhood was eerily quiet—the kind of silence that made each footstep echo. He dressed in a plain T-shirt and shorts, clothes worn for comfort rather than style, and stepped outside with a deep breath of the crisp air.
His sneakers hit the pavement as he began jogging, the rhythm steady at first. His muscles protested the early wake-up, but that only fueled his grin. This wasn't just about fitness; it was the foundation of everything.
A hero couldn't be weak, and he knew better than anyone how much groundwork mattered before power came into play.
"Just the beginning," he muttered under his breath, sweat already forming at his temple.
His lungs burned, his calves tightened, but he refused to slow down. This was the first day of what he'd already dubbed in his head his hellish exercise regime.
And hell or not, he wasn't going to quit.
TO BE CONTINUED