The Marine Headquarters : Marineford

Seeing his sneak attack blocked by me, who seemed like an ant in comparison, Aimu was enraged. He didn't realize yet that I had eaten a Devil Fruit and gained abilities, making me a much stronger opponent than he thought.

With Aimu's body already severely injured, I knew he wasn't in any shape to be my match. As he charged at me, I couldn't help but smile. I wasn't sure how I'd get Aimu to attack first, but now he'd walked right into it.

I quickly dodged his strike and used my ability to trap his feet, immobilizing him. If Aimu were in better condition, he might have been able to break free, but in his current state, he couldn't move.

That's when Aimu finally realized what was going on—that I'd eaten a Devil Fruit, just like him. Trapped and in danger, his instincts kicked in. Without thinking about the strain on his body, he activated his Devil Fruit powers, transforming into a massive black bear.

I had just eaten my Devil Fruit, so my control over my abilities was still weak. Meanwhile, Aimu's strength and defense skyrocketed in his bear form. He broke free from the restraints around his feet with barely any effort. But I could see it—he was running out of time. His body couldn't handle much more, so he needed to take me down fast.

"You little brat! You ate my Devil Fruit! I'm going to kill you!"

Despite his fury, I stayed calm. I knew Aimu's condition; if I could just survive his initial attacks, he wouldn't last much longer. I set up a series of spatial barriers between us and surrounded myself with several layers of shields.

But Aimu was too strong. He tore through the barriers like they were nothing. In an instant, he was in front of me, and before I could react, his fist was coming straight for my face. I quickly jumped, using a spatial fulcrum to launch myself behind him. I had a set of wooden spikes ready and thrust them into Aimu's eyes.

He howled in pain, but even then, he managed to land a powerful punch to my stomach. The shield I had up shattered, and I was sent flying.

Blood sprayed from my mouth as I flew through the air. I managed to form two shields to break my fall, but I wasn't quick enough to make a third before I crashed into the wall.

Boom!

I collapsed against the wall, clutching my chest, barely able to move. Aimu, now blinded in one eye, was furious. He approached me slowly, his rage radiating off him. His fist raised, he sneered, "You're going to die here with me, kid."

I coughed up blood but smiled weakly. "I'm not ready to die. Not with you."

Aimu hesitated for a second, sensing something wasn't right. But he shook it off and swung at me one last time. Just as his fist was about to connect, he froze. Blood began to drip from his mouth.

A large iron spike had pierced through his head, killing him instantly.

I had noticed the iron thorn hanging above Aimu and used my powers to contruct a disc to cut the rope holding it in place, causing it to fall and impale him.

As Aimu fell to the ground, my body finally gave out. The pain and exhaustion caught up to me all at once, and I blacked out.

Later, Garp stood nearby with a man in a suit, watching me.

"What do you think of this kid?" Garp asked.

The man studied me before answering, "He's got a strong will, he stays calm in the face of danger, and his combat instincts are sharp. He's not afraid of death and already has strong abilities. He's got all the qualities needed to become powerful."

Garp shook his head. "You forgot one thing—he's got a grudge against pirates."

He continued, "This kid's potential is immense. If we train him in the Navy, he'll become a force to be reckoned with."

 _________________________

After receiving the doctor's daily examination, I lay in bed, bored. The day I killed Aimu, I had passed out from exhaustion, and when I woke up again, I was already in a hospital, covered in bandages. After asking a nurse, I learned that I was at the Navy headquarters.

I had been here for over half a month now, and my injuries were almost fully healed. During this time, I'd managed to piece together the era I was in. It was now ten years after the death of the Pirate King, Roger. The entire Grand Line was balanced by the three great powers: the Seven Warlords, the Four Emperors, and the Navy. This meant it was ten years before the story of One Piece began, and Luffy was only seven years old.

I realized this gave me a buffer. I had a solid ten years to improve my strength before the plot even began. That should be more than enough time to ensure I could protect myself in this world.

I didn't know for sure, but I had a feeling Garp had brought me here. I was staying in a private ward, one only reserved for important naval personnel. Over the past fortnight, I'd had a chance to observe a lot of the Navy's headquarters. The sheer power they held was overwhelming. In just one month, I had seen hundreds of people with Devil Fruit abilities, and they weren't even actively fighting.

Right next to the hospital, I watched as more than 500 elite soldiers practiced "Soru," one of the Six Powers. It was humbling to see the real strength of the Navy up close. The Navy wasn't just any ordinary force—it was backed by the entire world, with countless resources fueling the training of powerful fighters.

I made up my mind then: I would join the Navy. Their training system was top-notch, backed by nearly limitless resources, and most importantly, no matter how strong I became, I could always find someone to challenge me and push me further. It was the perfect place for growth, and for someone like me, it was exactly what I needed to hone my abilities.

But the real question, the elephant in the room, was my Devil Fruit. Its appearance had been striking—a large, red apple with intricate swirling patterns on the skin. If I remembered correctly, Bartolomeo's Bari Bari no Mi from the canon had more of a bluish hue, which meant my fruit could be something different. I was sure the Navy had a Devil Fruit encyclopedia stashed somewhere, and I'd need to check it out later to learn the specifics.

From what I'd figured out so far, the fruit gave me the ability to create and manipulate barriers made of energy. They weren't the hard, transparent structures like Bartolomeo's; mine resembled red, psychic-like projections, almost like something straight out of Psylocke's powers from Marvel. This opened up a world of possibilities for how I could develop my powers, and I knew I had to approach it strategically. So far, I broke it down into four categories:

Defense: I could generate barriers to shield myself and others from virtually any form of attack—whether physical, energy-based, or otherwise. These barriers seemed nearly impenetrable.

Offense: The barriers could be turned into weapons. By sharpening their edges, I could slice through objects or opponents with precision. They could even act as piercing spears when needed.

Movement: Using the barriers for mobility seemed possible too. I could form platforms mid-air, allowing me to jump higher or even propel myself through the air. This would give me an edge in terms of speed and agility.

Confinement: Perhaps one of the most strategic aspects was the ability to trap my enemies. By encasing them in barriers, I could immobilize or confine opponents, controlling the battlefield and limiting their options.

The Navy headquarters was clearly the ideal environment for me to train. It wasn't just the resources; it was the access to knowledge—precious documents that could help me understand this world and its dangers, giving me the tools to survive and thrive. With the time I had before the canon timeline began, I would focus on growing stronger, mastering these powers, and preparing for the future that lay ahead.

Click...!

The door to my hospital ward creaked open from the outside.

In walked an old man dressed in a vice admiral's uniform. It was none other than Garp, the Navy hero. It had been over half a month since he dropped me off at the hospital, and this was his first visit.

Frankly, I'd grown bored during those long days. If Garp hadn't shown up today, I was already planning to go look for him myself.

Seeing Garp now, he didn't look as old as he did in the comics. He must've been around 50 years old at this point, but honestly, he looked even more energetic than he did in his twenties or thirties. He didn't bother asking how I was recovering. Instead, he walked straight to the window, gazing out at the naval soldiers sweating through their training.

Without turning to face me, he asked, "What do you think of those soldiers out there?"

I suddenly realized why he was here. Garp wanted me to experience the atmosphere of the Navy headquarters for myself. Playing along, I replied, a little sarcastically, "Well, it *is* the Navy HQ. These soldiers are a cut above the rest, but it feels like they're not really doing much, despite their strength."

Garp didn't seem bothered by my sarcasm. Instead, he laughed and—before I knew what was happening—appeared right in front of me. I recognized it immediately: "Shave," one of the Rokushiki techniques. With no warning, he punched me in the head.

I barely had time to react. I quickly threw up three energy shields over my head, using the power I'd been practicing for weeks. Since arriving at the Navy headquarters, I hadn't wasted a single day. After more than half a month of intense focus, I'd become faster at deploying shields, and their durability had increased too.

But none of that mattered to Garp. His punch tore through my defenses like they weren't even there, hitting me dead-on. The impact sent me flying off the bed, smashing me into the wall. I barely managed to throw up another shield around myself, or else hitting the wall would've left me in agony.

Clutching the growing lump on my head, I yelled, "What the hell, old man?! What's your problem?"

Garp didn't respond. His face remained expressionless as he used "Shave" again, coming at me for another punch.

I wasn't about to just sit there and take it. I retaliated, flicking my fingers and sending a cluster of small red spheres toward him. This was one of the new moves I'd developed while in the hospital—tiny, compressed balls of space that packed the power of cannonballs when they exploded.

But Garp? He dodged them effortlessly. His speed didn't slow down for a second as he weaved through the explosions, closing the gap between us. I muttered to myself, "That's... haki."

Despite all my effort, the result was inevitable. Garp hit me again, launching me back into the wall. My attack hadn't done much except blow up half the ward. The explosions triggered the alarms, and soon enough, the entire Navy HQ went into high alert. Within minutes, a swarm of heavily armed soldiers surrounded the hospital. The Navy's efficiency was... impressive.

A rear admiral led the charge, barking orders to the soldiers, "Prepare to breach the hospital! Evacuate civilians!"

Just then, Garp strolled out of the destroyed ward, dragging me behind him in my hospital gown.

The rear admiral saluted and asked, "Vice Admiral Garp, is there a criminal who infiltrated the HQ?"

Garp, looking a bit embarrassed, scratched his head and laughed awkwardly. "Nah, I was just teaching this kid a lesson. Things... got a bit out of hand. Everyone can stand down."

The soldiers looked at each other in disbelief. "-------"

Later, after the chaos died down, I woke up to find myself lying on a rock near the port. Garp sat beside me, staring out at the bustling docks, lost in thought.

I rubbed my aching head and asked, "Old man, why'd you bring me out here?"

Instead of answering directly, Garp asked, "What do you think of this port?"

I looked around, taking in the scene. It was dusk, and the entire sea shimmered with a golden glow. The port was alive with activity—ships were coming and going, workers were unloading cargo, and fishing boats were returning from the sea. There was a peaceful, bustling energy in the air.

"It's prosperous, peaceful, secure... You don't see a port like this every day," I replied.

Garp chuckled. "You're right. This is one of the safest ports in the world, and do you know why? Because it's right next to Navy Headquarters. No pirate dares to come near here."

I grinned knowingly. "So, is this the part where you try to recruit me into the Navy?"

Garp sighed and shook his head. "You're too sharp, kid. Yes, I want you to join the Navy."

I'd already decided that I wanted to join, so this was right up my alley. "If I say no, are you gonna let me leave?"

Garp gave a silent nod, but I could tell he didn't expect me to refuse.

I shrugged. "Well, in that case, I'm in. I'll join the Navy."

But then I smirked and added, "On one condition: you have to personally train me, old man."

Garp seemed surprised at first, but then he laughed. I guess he was expecting some outrageous demand, but this? This was easy for him. I could tell he'd already planned to train me himself. Nodding without hesitation, he agreed.

Grinning, I stood up, ready for my next chapter. I bowed my head in mock ceremony and said, "I, Kai Miller, officially declare Garp as my supreme master."

Just then, a Navy soldier ran over, out of breath. "Vice General Garp! The Fleet Admiral wants to see you immediately."

Garp stood up, cracking his knuckles. "Alright, kid. Being my apprentice isn't gonna be easy. Prepare yourself for some devil training starting tonight."

I smiled, knowing full well I was in for the hardest training of my life. But I was ready.