Exactly six months had passed since the fateful "Diagnosis Day," as my mind had sarcastically—but deservedly—dubbed it. Six months of a subtle yet relentless persuasion campaign, during which I managed to convince two legitimately concerned mothers that the single most effective solution to the rampant systemic discrimination in modern hero society was, surprisingly, a mandatory daily routine of morning cardio. It was a ridiculous plan on the surface, but it worked.
The crisp morning air, still holding the slight chill of dawn, brushed against my face with a familiar welcome. My sneakers, which would soon need replacing, hit the pavement of the neighborhood park paths with a hypnotic cadence. Breathe in, breathe out. A steady, easy rhythm, the soundtrack to an unexpected reincarnation.
In my previous life—the one spent in a world without Quirks or explosions—I was the very definition of physical mediocrity. I was... painfully normal. If I had attempted a morning jog, a side stitch would have stopped me within three minutes, and embarrassment would have done the rest. An attempt at a somersault would have resulted in a sprained neck or, worse, public humiliation. My reflexes were those of a lazy snail: seeing a glass fall meant my brain registered the "oops" two seconds after the glass shattered against the kitchen floor.
But this body... this body was a biological masterpiece, a piece of genetic engineering that bordered on the absurd.
The feeling was comparable to going from driving an old family sedan, with completely misaligned steering and an engine that coughed more than it roared, to piloting a Formula 1 car, gleaming and fresh off the production line. The difference wasn't just noticeable; it was existential.
Now, with an almost insulting ease, I leaped over a tree root jutting out of the path without breaking my stride, landing with a feline softness that shouldn't be possible for a barely four-year-old child. It wasn't just the Explosion Quirk giving me this edge; it was Katsuki Bakugo's innate biology. His muscle fibers were built for power, his sense of balance was impeccable, and his hand-eye-foot coordination was tuned to an elite level by genetic design. Everything about him was perfected.
I began to understand why the original Bakugo, the one from the manga I knew, was so arrogant and explosive. When the physical world obeys your every whim and command without the slightest effort, without flaws or hesitation, it's too easy to start believing you are a superior being, almost a god. My brain sent a motor command, and the body executed it with pinpoint precision. There were no neural delays, no muscular clumsiness, no dreaded "friendly fire" from a body betraying you.
It was an intoxicating feeling. And yes, it was dangerously addictive.
"Wait... wait, please!"
The breathless voice, almost a gasp for help, from Inko Midoriya violently pulled me from my pleasant biological analysis and philosophical ramblings about physical superiority.
I slammed on the brakes, spinning on my heels with a motion so fluid and fast that an outside observer would have sworn my feet never even touched the ground. Behind me, the self-proclaimed "Future Hero Defense Squad" (name still pending approval, despite my complaints) was in various, pitiful states of physical deterioration.
Izuku was running with his face red as a ripe tomato, his little arms pumping in an exaggerated and inefficient manner, but with a fierce, admirable determination shining in his green eyes. Right behind him, my mother, Mitsuki, jogged with an ease that was insulting to the rest of the group, shouting encouragement (or threats, the line was terribly blurry when it came to her) that seemed to give Izuku new energy. And, unfortunately, at the back of the formation, poor Aunt Inko looked to be one step away from imminent collapse, her lungs burning, but she kept moving her legs with admirable tenacity.
"Come on, Inko!" my mother yelled, slapping the other woman on the back with a sound like a gunshot that nearly sent her face-first into the dirt. "If these brats can handle it, we can handle anything! Burn off that katsudon fat once and for all!"
"M-Mitsuki, have mercy!" Inko groaned, bending over slightly.
I smiled wryly at the scene. At first, Inko only wanted the kids to train (meaning, for me to train Izuku), but I subtly reminded her that future heroes needed healthy, active role models. Now, she was steadily losing weight and gaining stamina she never thought possible, even if she complained with every step she took. It was a win-win.
Izuku finally caught up to me, resting his hands on his knees and breathing with a wheezing rhythm, like an old steam locomotive that had been climbing a steep hill for too long.
"Did I... did I catch you... Kacchan?" he asked between heavy gasps that stole his breath.
"Almost, nerd," I said, uncapping my water bottle and handing it to him. Of course, I wasn't going to tell him I had been running at 40% of my maximum capacity. Demoralizing him at this stage was pointless and didn't fit my plans.
While he drank greedily, I used the pause to start a series of dynamic stretches. I easily lifted one leg above my head, maintaining a perfectly stable and almost supernatural balance on the other. I was in an experimental phase. The original Bakugo, the one I had seen fight, used his hands for absolutely everything: main attack, mobility, defense. By necessity, this generated brutal tension in his shoulders and wrists (the constant recoil from the explosions was no joke).
But what if I shifted the paradigm and used my legs as thrusters and secondary weapons? What if I moved more like a rocket-propelled breakdancer, adopting Shinra Kusakabe's acrobatic style? For that, I needed two key things: a low, extremely stable center of gravity, and a core made of pure steel. And flexibility. A lot of flexibility.
"Wow! You're super flexible, Kacchan!" Izuku exclaimed, partially recovered, trying to mimic my stretch. The result was immediate and predictable: he fell right on his butt in the soft grass.
I laughed, a genuine chuckle, and offered him a firm hand to help him up. "It's a matter of balance, Izu. You have to learn to tighten your core."
"Alright, recess is over!" Mitsuki announced, coming up beside us with a scowl and showing zero signs of fatigue. She was a terrifying woman. "We're playing tag! But with special rules: whoever Katsuki tags has to do ten frog jumps as punishment!"
"Huh?!" Izuku squeaked, his previous determination replaced by adorable terror. "But Kacchan is too fast!"
"Then run faster, Deku!" I yelled, giving him a courtesy three-second head start before shooting off after him, my explosive speed already making a massive difference.
Izuku let out a high-pitched shriek—a delicious mix of terror and genuine laughter—and bolted down the park trails as if the devil were chasing him.
We weren't doing military push-ups under the sun. We weren't punching sandbags. To any observer, we were just four-year-olds playing freely in the park. To the untrained eye, we were simply having fun like any other pair of friends. But I knew the hidden truth. I was working on my sudden directional changes, my feline agility, and my explosive starting speed. Izuku, on the other hand, was working on his cardiovascular endurance, his lung capacity, and, involuntarily, learning how to run away from an imminent threat—a skill he would sadly need in the future.
I watched him laugh out loud as he deftly dodged a flowerbed and a tree, with Inko weakly cheering him on from a nearby bench where she had happily collapsed, accepting temporary defeat.
Enjoy it, Izuku, I thought, deliberately slowing my pace enough to almost catch him, missing by a hair, which made him scream with pure, overflowing excitement. Enjoy the fact that your lungs burn from running non-stop and not from cigarette smoke. Enjoy your legs aching from playing and not from broken bones caused by a villain.
There would be plenty of time to start training Muay Thai, Wrestling, or Krav Maga in a couple of years, when their bodies were a bit more resilient and formal training wasn't a danger. For now, the primary goal was to build the perfect engine before slapping the heaviest armor onto the tank.
"Gotcha!" I yelled, giving him a firm but gentle tap on the shoulder.
"Nooo!" he exclaimed, laughing heartily, throwing himself onto the grass with dramatic theatricality.
Yeah. This felt good. This was important. I could protect him. A little more time. A little more of this forced normalcy, and he would have a solid foundation.