— — — — — —
The next day, the chaos Leo caused still wasn't completely resolved, but none of that had anything to do with Kazuma anymore.
Those were Leo's problems. Kazuma had something far more important to handle—researching the reward he'd just received.
"Sage Art Training Method from Naruto… so basically the method for extracting Sage Chakra."
"The problem is… I don't use chakra. I use magic. There's no chakra for me to make it a Sage chakra."
Kazuma began studying the technique. After digging into it for a while, he realized that what he'd received wasn't exactly the original version—it had already been modified.
In the Naruto world, places like Mount Myoboku taught Senjutsu by absorbing natural energy from the environment, then mixing it with one's own chakra in specific proportions. The result was Sage chakra, a higher-quality energy that massively boosted ninjutsu, taijutsu, and genjutsu—tenfold, sometimes dozens of times stronger.
But that form of Senjutsu had a flaw: the user could only hold a limited amount of natural energy at one time, and once it ran out, they had to absorb more.
(At least that was true for Naruto. The First Hokage seemed different… that guy clapped his hands and entered Sage Mode instantly, fought for ages, and no one ever saw him run out.)
Kazuma's version, however, was a fundamental training method. Instead of absorbing natural energy from the outside, it directly transformed his own magic into pure natural energy.
Put simply: Instead of getting power from the world, it upgraded the quality of his own energy (Magic) from the inside out.
"Alright. Let's start. Maybe controlling my magic will be easier that way."
Kazuma found a quiet place surrounded by nature, sat down, and immediately began practicing.
The massive magic within his body gathered, condensed, compressed, and slowly regressed toward its most primitive state.
"Everything in this world contains magic. But in one of Fairy Tail's parallel worlds, magic doesn't exist at all."
"So is magic in this world unique?"
"But whenever I travel to other worlds, I never have trouble recovering magic… is that because of the system?"
As he trained, a question surfaced in his mind.
Why didn't his magic ever run dry when he visited other worlds? At first he assumed the system was helping. But now… he wasn't so sure.
"Natural energy contains every form of energy in the universe. Magic is just the part humans in this world happen to recognize."
"So it's not that other worlds lack magic… they just don't have this world's version of magic. They have other types of energy."
"All of them are essentially pieces of natural energy. No matter the type, magic is just another form of energy."
(Einstein also said: Energy cannot be created or destroyed, it can only be changed from one form to another.)
The modified Sage Art Training Method didn't require absorbing external natural energy, so there was no risk of being overwhelmed or turned to stone.
After all, being assimilated by your own energy was impossible. If that ever happened, the chicken-or-egg question would finally have an answer.
...
While pondering, an hour slipped by.
"…Only this tiny bit after a whole hour?"
He looked at the faint speck of natural energy in his body.
It was clear that changing all his magic would take a long time.
"Let's test this energy on something. Is pure mean powerful?"
He felt like a kid holding a hammer for the first time—everything looked like a nail. After walking around for a bit, he found a huge boulder.
He placed his hand on the stone. Natural energy gathered and burst outward.
Boom!
The boulder exploded instantly.
"So that's how it works! I get it now!"
Natural energy behaved completely differently from magic. The moment he released it, that single bit of energy instantly began dragging in natural energy from the environment, multiplying itself.
That was the biggest difference from magic—amplification.
"And after I used it, it recovered on its own not long after."
He sensed natural energy slowly returning within him and nodded. Clearly it wasn't a one-time resource.
"Keep going."
Kazuma sat and trained for several more hours. Natural energy grew within him, and the conversion rate began to speed up.
"I didn't notice earlier because the amount was too small, but now it's obvious."
"These natural energies are constantly strengthening my body… making me tougher, and more attuned to natural energy."
"This is basically… a man-made Sage Body?"
He could feel natural energy roaming through his body, circulating through every corner. Each full circuit made him physically stronger and increased his training speed.
His physique was changing.
"I feel stupidly strong right now…"
His fists actually felt itchy. This was usually where a villain showed up to get beaten.
"Too bad life doesn't care about dramatic timing. Whatever… back to training."
He spent a few more hours practicing until he fully adapted to the method. Once mastered, the process became passive—he could produce natural energy while eating, walking, or sleeping.
Gurrrr~
"Man, I'm starving. Time to hit the guild."
He'd trained so long he hadn't eaten all day. When his focus finally broke, his stomach was already protesting violently.
---
Inside Fairy Tail—
"Kazuma… are you sure you're okay?"
"Should we get a doctor?"
Mira's warm smile had disappeared, replaced by pure concern as she watched Kazuma devour plate after plate.
"I'm fine. I'm perfectly healthy. Why would I need a doctor? Oh, Mira, bring me another tub of rice. I'm starving today."
He tossed the empty plate onto the nearby mountain of dishes. Maybe he trained too hard today—he felt starving.
"You're not hungry—you've gone insane! Do you know how many times you've asked me for refills already?!"
Mira glanced at the towering pile of plates and bowls beside him. She'd seen big eaters in the guild… but nothing like this. She was genuinely worried he might explode.
"Not that many, right?"
He was too focused on eating to keep count.
"That was the twenty-fifth refill! You've already eaten almost everything the guild stocked today!"
Mira stared at Kazuma's perfectly flat stomach, unable to hold back her shock.
"I really ate that much?"
Kazuma turned toward the mountain of bowls and chopsticks. Okay, that did look like a lot… but somehow he still didn't feel full.
"The natural energy's increasing faster… and my body feels stronger than ever. So this is the price of getting stronger. I'm becoming Monkey D. Kazuma..."
He checked his condition. Most likely the natural energy reinforcing his body had drained his physical nutrition. And because natural energy had such powerful assimilation and decomposition properties, everything he ate was instantly converted into energy.
That was why no matter how much he ate, he still felt hungry. His magic reserves were enormous, but his body's nutritional tank was completely empty.
"Are you really okay? Did someone curse you to turn into a bottomless pit? Should we get someone to look at you?"
Mira grabbed his hands, speaking with heartfelt seriousness. "Don't worry. I'm sure it can be cured."
"Mira, come on, it's not that serious. I just got hungrier. It's not like I went bald."
"If I can eat, I'll eat. It's not like I can't afford it. Bring out whatever ingredients we still have. I'm paying twice the price."
Compared to going bald, eating a little extra was nothing. Especially since he wasn't short on money.
"…Fine. I'll bring everything out."
Mira sighed and hurried to the back. But it didn't take long before even the remaining ingredients were gone.
"I'll just keep eating outside then."
Kazuma placed his dishes on the counter, walked out of the guild, and found another restaurant to continue eating.
"Haa… Kazuma really has turned into a walking stomach."
Mira sighed, then perked up. "But that means I can try making more new dishes from now on."
"I won't have to worry about the cost or wasting food anymore. That's actually pretty great."
Mira loved cooking more than anything—especially experimenting with new recipes. The only problem was she could never finish everything she made. Even Elfman couldn't handle the leftovers. One month she'd even fed him so much he turned into a chubby ball.
It took him half a year of training to get back to normal.
...
Meanwhile, Kazuma had settled into a restaurant outside the guild and didn't stop eating until seven in the evening.
"No customers left? Good. You two guard the entrance. You two stand by the restroom. This kid's eaten too much. If he tries to dine-and-dash, I'll go bankrupt. Don't let him escape!"
The boss eyed Kazuma, who was still eating without pause, and felt an ominous sense of danger. He immediately ordered his staff to block every exit.
---
By nine o'clock—
"Boss, I… I don't think he's trying to skip the bill. I think he's actually trying to eat us out of business."
"All the ingredients we bought today… they're gone. Do we… still keep serving him?"
The chef walked out looking helpless.
"Serve him! We still have some frozen stock. Bring it out. I've run this restaurant for years. I've never seen someone this outrageous!"
The boss slammed a fist into his palm. As a restaurant owner, he had a matter of pride: no customer should leave his place unsatisfied.
"Boss, frozen ingredients… isn't that against our whole fresh-daily theme?"
The chef hesitated. He actually had professional ethics. Passing off frozen items as fresh felt a bit shady.
"Relax. I'm not a crook. They've only been frozen a few days. Still perfectly good. And I'll tell him upfront. Everything from now on is half-price."
The boss explained the situation to Kazuma, got his approval, then gave the chef a thumbs-up.
"I'm fired up now!"
The chef's spirit ignited. His pride as a cook was on the line. No way was he letting a customer leave hungry.
...
By eleven—
"Boss… I… I can't carry plates anymore. Look at my hands, they're shaking…"
"I only get paid this much a month. Please don't work us to death!"
The servers were trembling from head to toe. For hours straight, none of them had stopped moving. Serving, clearing, serving, clearing. Their bodies were about to give out.
"Tsk. Young people these days can't handle anything."
"Sit down and watch. Let me show you how it's done."
"When I was your age, I handled an entire restaurant by myself. Not a single moment to rest. But I never gave up. See these muscles? These were carved out back then!"
The fifty-year-old boss rolled up his sleeves, revealing lean, hard muscle. For his age, it was impressive.
Then he went to work.
One man doing the job of five or six, and faster than all of them too.
...
But by midnight—
"Boss! Are you okay?!"
"I… I'm fine… help me up… I… I can still fight…"
The boss lay on the floor, limbs shaking uncontrollably. If he were ten years younger, he could've held out. But age had finally caught up.
"Boss, please rest! We get it, okay? You're amazing! Don't push yourself anymore!"
The servers surrounded him, tears streaming down their faces. They had never seen such unbreakable will.
"Boss… we understand now. We finally get what dignity and pride a server carries…"
"That's… good. I believe every one of you has the potential to become a restaurant owner. Young men… young ladies… keep working hard."
With a satisfied smile, he said his piece, then tilted his head back and stopped moving.
"Boss!"
The staff wailed dramatically.
"…What are they doing? "
Kazuma finally felt full. His body's missing nutrients were replenished. He looked at the collapsed boss.
"So… who's taking my payment?"
"HERE!"
The "unconscious" boss shot up the instant he heard the word "payment," trembling as he staggered over to Kazuma.
He took the gold Kazuma pulled from his Treasury. The weight nearly made the exhausted man collapse again.
"This is for the meal. And this extra bit is your tip. You people are dramatic, but the service was really solid."
Kazuma paid triple the bill. With service like this, a big tip felt deserved.
"Thank you for dining with us! We look forward to your next visit!"
Tears streamed down the boss's face. Money didn't matter anymore. What mattered was that he'd upheld his honor as a restaurant owner.
He had fed the customer. The customer was satisfied. That was everything.
Supported by his staff, the boss personally escorted Kazuma to the door and repeated a line he had said countless times in his life: "Goodbye~ Please come again."
"Alright. I'll come again tomorrow. Your food's pretty good."
Kazuma said casually, then turned and left. It was late. Time to head home and sleep. He had things to do tomorrow.
"Come… again… tomorrow…"
The boss stiffened, then collapsed backward like a felled tree.
Right now he deeply regretted ever opening his mouth.
His mind was filled with one phrase: "I'll come again tomorrow."
.
.
.