"I Reincarnated in Boku no Hero but They Forgot to Give Me a System"

Chapter 31 – The Light of Heroic Haki

The morning sun slowly rose over the horizon, casting long shadows across the grassy field behind the mansion. Aoi stood barefoot on the training grounds, his shirt soaked with sweat, fists clenched and bruised, facing a massive boulder.

He was alone.

As usual.

His breathing was steady, eyes focused, body covered in small cuts and scratches. A faint blue glow pulsed around his arms, slowly healing all his wounds.

"Again..." he muttered.

Then he struck.

His fist collided with the rock, echoing with a dull thud. At the moment of impact, a burst of blue flames engulfed his hand—but instead of burning the stone, they fizzled out, dissolving like mist.

No damage.

Aoi looked at his hands. They weren't getting hurt as easily anymore. And then he understood: the stronger his body became, the harder it was to break it—which meant that over time, his growth would slow down.

There would come a point where only battles against extremely powerful enemies could damage him enough so that he could heal and grow stronger.

Aoi gritted his teeth, pulling his arm back and flexing his fingers.

"But before that… I need to reach at least half of All Might's power before the main story even begins. Otherwise, I might not even be worthy of the final battle. I'm not betting on this world repeating the same story where Izuku always saves the day."

He stretched his arms, thinking. Since his physical strength was starting to grow more slowly, it was time to focus on the Haki techniques he had created—his own invention, inspired by One Piece.

Looking at the flames in his hand, he whispered:

"If I can compress it... keep it thin, stable, dense..." — his eyes burned with determination — "...then I'll have more freedom to use my flames beyond flying and healing others."

This was his version of Armament Haki.

If he could bring this power as close as possible to its One Piece counterpart in this world, it would be a powerful asset for the battles to come. So he started again, punching the massive stone in front of him.

Punching. Pushing. Sweating. Minutes turned to hours. The rock remained unmoved, but his presence on the field grew stronger with each strike.

Then—

"You really train like a maniac, huh?"

Aoi didn't stop immediately. One more punch. Then another. He only turned after the third.

Mirko stood at the edge of the field, arms behind her head, casually chewing on a carrot. She didn't seem impressed, but her ears twitched with curiosity.

"Endeavor's kid, right? Why are you doing all this alone? Shouldn't you be learning flashy fire moves like your dad?"

Aoi paused, breathing heavily, sweat dripping down his face. He raised his hand, letting the blue flame softly glow in his palm.

"Because... my fire doesn't burn."

Mirko raised an eyebrow.

"Say what?"

"It doesn't produce heat. Nothing destructive. All it does is speed up healing—mine and others'."

He closed his fist; the blue glow intensified.

"My fire can't burn anything. Kinda ironic, huh? A flame that can't do the most basic thing—burn."

Mirko blinked, surprised, and shrugged.

"Even so, with a quirk like that, you could be the next Recovery Girl. Everyone loves healing heroes."

Aoi shook his head, still staring at the stone.

"I can't work like her. My flames are tied to my emotions. I can't heal people I have any negative feelings toward. And it takes way more out of me to heal others than to heal myself. So... I'm not cut out to be that kind of hero who saves everyone."

He turned to her, his expression sharpening.

"But then I had an idea. You know, Mirko... before quirks existed, no matter how much someone trained, there was a max limit they could reach. When quirks came along, people started getting stronger and stronger, like those limits vanished. But they didn't. The limits are still there—quirks just increase how far someone can go."

He stepped forward, blue flames rising over his arms, chest, and shoulders—pulsing like a living heartbeat.

"That's when I used my mind to create techniques that support this body—this body that's getting stronger and stronger."

As Aoi spoke, a sliver of his emotions fused into the flames, and for a brief moment, Mirko felt it—a crushing will to win that made her clench her fists on instinct.

She felt it—the pressure.

It wasn't just heatless flames.

It was something deeper: a presence, a force. The ground trembled faintly beneath her. The air thickened. Trees shivered without wind.

Aoi's voice dropped to a powerful whisper:

"I call this technique… Heroic Haki."

Mirko's ears twitched. Her instincts screamed to prepare. This boy wasn't bluffing. Something real was happening here.

He looked up. His eyes glowed like living blue fire.

"This power is the fusion of my flames and my body—trained to surpass physical limits."

Silence.

Then, Mirko laughed—low and genuine.

"Heh... now you're talking." — She jumped onto the boulder he'd been punching all morning and sat, still chewing her carrot. — "Looks like you're not just some brat. I guess I'll have to start taking you seriously."

She leaned back, a wild smile on her face.

"Alright, brat. You've got my attention now. Let's see how far this 'Haki' takes you."

From a distance, Ryukyu and Midnight stood beneath a tree, watching.

Ryukyu stared thoughtfully.

> "This boy... to have that level of strength at his age… Who would've thought someone with a healing quirk could use it for such reckless, self-destructive training just to break his own limits."

Midnight crossed her arms and smiled, amused.

> "Well… it looks like it was his will that made this idiotic plan actually work. But honestly... it's a shame. I wanted him to become a healing hero. We have so few with quirks like that."

Then Aoi called out to Mirko, asking her to climb on top of the stone.

With her seated on it, he placed the giant boulder on his back—and began doing push-ups, lifting several tons with sheer strength.

Mirko, sitting atop the rock and watching him, smirked with wild delight.

"Looks like I finally found myself a proper training partner."

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