It was a fine day out on the open seas, the transport vessel steadily making its way towards a Marine base. Among the crew, a young man carried out a humble task, diligently cleaning up the mess. This particular young man was none other than Monkey D. Luffy, though today he was without his signature straw hat, a gift he had never received in his lifetime. Fate had yet to bring him face to face with Red Hair Shanks; their paths had narrowly missed crossing. Unlike the Luffy known for embracing the life of a pirate, this version had charted a different course, driven by a deep affection for his grandfather and an aversion to banditry. He now held the rank of a Lieutenant Junior Grade in the Marines, operating covertly to root out corruption and other issues within the organization. His unassuming position helped him maintain a discreet presence.

Luffy envisioned a straightforward journey to the Marine Base, a meeting point with his brother Ace, who had ventured ahead. Like Luffy, Ace had also found his place within the Marines, fueled by a profound resentment for their shared father and a profound respect for their grandfather. Together, they undertook missions aimed at addressing challenges that plagued the Marines. Amid the rhythmic sounds of cannon fire striking the ship's hull, Luffy sensed the imminent attack. With caution in his steps, he prepared to emerge from his quarters, mindful of the need to conceal his true identity. Revealing himself prematurely could tip off the Shell Town Marine Base, jeopardizing his quest for uncovering the extent of corruption within their ranks.

As Luffy lingered, the creak of the door announced a new presence. A timid figure with pink hair entered, appearing both flustered and apprehensive. "Um, excuse me, but what brings you here? You don't strike me as a pirate," Luffy inquired, regarding the pink-haired youth with curiosity.

"I'm Coby. I'm not a pirate; circumstances forced me into this role as their deckhand," the newcomer named Coby explained, his gaze fixed on Luffy. "These pirates are ruthless, led by the fearsome Alvida and her iron mace."

Luffy paused briefly, recognition dawning upon him. Alvida was a minor captain within the East Blue. Nodding thoughtfully, he responded, "Don't let others trample over you just because you're afraid. Stand up for yourself."

Before long, the clash of footsteps signaled the approach of more pirates. Luffy skillfully evaded their attacks, swiftly neutralizing them without breaking a sweat.

Satisfied with the encounter, Luffy introduced himself, "I'm Luffy, Monkey D. Luffy. If you want safety, stick with me for now." He motioned for Coby to follow.

"I'm Koby. You're right; I need to find my courage. It's just... it's not that easy," Koby admitted, his eyes meeting Luffy's.

Luffy's response was firm yet compassionate, "Courage isn't a choice; it's a state of being. You either possess it or you don't. Face challenges head-on; the alternative leads to a slow, regretful demise. Embrace bravery, even if it entails risks. Dying with honor is preferable to living in shame."

Ascending to the deck, Luffy confronted the ship's commander, Alvida, a portly woman reveling in her recent triumph over a civilian vessel. Unimpressed by her antics, Luffy engaged her attention alongside Koby.

"Who's this, Koby? A newfound friend?" Alvida jeered, her gaze fixated on Koby.

"This is Luffy, and I'll become a Marine. I'll capture you and every other pirate out there," Koby asserted defiantly.

Koby's declaration surprised Luffy, prompting a glimmer of hope in his assessment of the young man. Facing Alvida and her crew, Luffy demonstrated his resolve. He summoned his armament haki, reinforcing his arms to counter Alvida's iron mace. A single powerful punch sent Alvida sprawling, while Luffy smoothly dispatched the remaining attackers. As the chaos subsided, it became evident that the ship's course to Shell Town was uncertain.

"Koby, join me. We're heading to Shell Town, where a Marine base awaits," Luffy proposed, indicating a commandeered pirate boat.

Koby, slightly taken aback, complied, embarking with Luffy on the stolen vessel. Luffy's decision prioritized the investigation of the corrupt Marine base over collecting the bounty on Alvida, underscoring his commitment to his new role.

"Off to Shell Town. We'll maintain a discreet presence," Luffy advised Koby, setting their course.

"Wait, are you a pirate?" Koby inquired, uncertain of Luffy's allegiance.

"No, I'm a Marine. Our goal is to uncover the truth behind the chaos in this town. Remember, this remains confidential," Luffy affirmed, leaving Koby intrigued by the unfolding partnership.

As the stolen pirate boat sailed towards Shell Town, Luffy and Koby found a moment to talk in hushed tones. The sea breeze ruffled their hair as they exchanged thoughts on the town's predicament.

"Koby, this place seems off, doesn't it?" Luffy mused, his eyes scanning the horizon.

"Yeah, there's an air of fear and tension. People seem oppressed, like they're hiding something," Koby replied, his voice tinged with concern.

Luffy leaned against the side of the boat, gazing at the water. "I've heard rumors about Axe Hand Morgan, the Marine in charge here. They say he's corrupt and ruthless, abusing his power."

Koby's eyes widened, his curiosity piqued. "Corrupt? But he's a Marine, supposed to uphold justice, right?"

Luffy nodded solemnly. "That's what they should do. But sometimes, power can corrupt even the best intentions. If Morgan's abusing his authority, then we need to find out the truth."

Koby hesitated, frowning. "But how? We're just two guys on a stolen boat. We can't take on the entire Marine base."

Luffy grinned, his confidence unwavering. "We don't have to take them all on at once. We start by gathering information, talking to the locals, and finding out what's really going on. Once we have enough evidence, we'll figure out our next steps."

Koby considered Luffy's words, a glimmer of determination in his eyes. "You're right. We need to be smart about this. If we expose the corruption, it could make things better for the people here."

"Exactly!" Luffy exclaimed. "And if we're careful, we can avoid drawing too much attention to ourselves. We'll blend in, gather information, and when the time is right, we'll confront Morgan."

Koby's resolve solidified as he looked at Luffy. "I'm with you, Luffy. Let's uncover the truth and bring justice to this town."

Luffy clapped Koby on the back, a grin spreading across his face. "Great! We make a good team, Koby. Together, we'll show them that not all Marines are corrupt."

Luffy decided to gather more information by visiting a local tavern in Shell Town. The atmosphere inside was lively, with patrons sharing stories and laughter. He leaned against the wooden counter, nursing a drink as he listened intently to the conversations around him.

Amidst the chatter, his attention was drawn to a young girl sitting alone at a corner table. She had a melancholic look in her eyes as she spoke softly to herself, recounting a tale that piqued Luffy's interest. Sliding onto an empty stool nearby, Luffy subtly tuned in to her words.

"There was this man," the girl began, her voice tinged with sadness. "He was kind, and he helped me when no one else would. He protected me from Captain Morgan's son and his ferocious dogs. But now he's tied up, awaiting his fate."

Luffy's curiosity deepened. He sipped his drink and glanced at the girl, wondering if he should join the conversation. Before he could decide, the girl continued, her words heavy with emotion.

"They said he went against Captain Morgan's orders, defying his authority. But he only did it to save me," she murmured, her gaze fixed on an imaginary point. "He didn't deserve this. He risked his life for mine."

Luffy's grip on his glass tightened. He recognized the injustice in the girl's words, and his resolve solidified. This was the corruption he had suspected – the abuse of power that needed to be exposed. Determined to offer his assistance, he turned to the girl.

"Hey," Luffy spoke gently, catching her attention. "I couldn't help but overhear your story. I'm Monkey D. Luffy, and I want to help. Tell me more about this man and what happened."

The girl looked up, surprised by Luffy's offer. Her eyes met his, and she hesitated before finally speaking. "His name is Roronoa Zoro. He's a swordsman, and he saved me from those dogs. But now he's being held in the Marine base, facing punishment for doing the right thing."

Luffy nodded, his expression determined. "I'll make sure he gets out of there. We'll expose the corruption and bring justice to this town."

The girl's eyes widened, a glimmer of hope entering her gaze. "You'd really do that? But Captain Morgan is powerful, and his son is ruthless."

Luffy grinned, his confidence unwavering. "Don't worry, I've taken on tougher opponents than them. We'll put an end to this together."

The girl's lips curved into a small smile. "Thank you, Luffy. You're our only hope."

Luffy finished his drink and stood up, his gaze fixed on the Marine base in the distance. "Let's go, Koby. We've got a swordsman to rescue and a corrupt regime to take down."

Luffy strode purposefully towards the headquarters, his determination unshaken. He had a burning desire to uncover the truth and make things right in Shell Town. As he arrived at the imposing building, he spotted a figure tied up near the entrance. It was Roronoa Zoro, the pirate hunter, restrained and seemingly at the mercy of the oppressive regime.

Turning to Koby, Luffy gestured for him to stay put. "Wait here, Koby. I'm going to talk to that guy." His voice carried an air of confidence and conviction as he approached Zoro.

"Hey there," Luffy greeted, his tone friendly yet resolute. "I'm Monkey D. Luffy. I heard you're in a bit of a tight spot. Mind if I hear your side of the story?"

Zoro, his eyes focused and his expression unwavering, met Luffy's gaze. "I'm Roronoa Zoro. I did what I had to do to protect that girl. I can handle whatever punishment they throw at me."

Luffy nodded, understanding the situation better now. "Sounds like you're a tough guy. But you know, you don't have to face this alone. I'm putting together a crew, and I could use someone with your skills."

Zoro's eyebrow raised in surprise. "A crew? Are you a pirate?"

Luffy grinned, a glint of determination in his eyes. "No, I'm a Marine. I'm on a mission to root out corruption and bring justice to the world. We need strong people like you to make that happen."

Zoro's gaze held a mixture of contemplation and resolve. "I appreciate the offer, but my goal is to become the strongest swordsman in the world. I'm not interested in joining any group."

Luffy's grin widened. "That's a great goal. And you know what? I've got my sights set on becoming the strongest Admiral in the Marine fleet. I'll wipe out corruption and make the Marines a force for good. So, you can chase your dream while still helping to make the world a better place."

Zoro studied Luffy, a hint of a smile tugging at the corner of his lips. "You've got big ambitions, I'll give you that."

Luffy's voice carried conviction as he responded, "That's right. So, what do you say, Zoro? Will you join us in taking down corruption and making a difference?"

Zoro's gaze locked with Luffy's, a newfound determination burning within him. "I'll join your crew, but don't think for a second that I'm following your orders. I'll do things my own way."

Luffy laughed, his excitement evident. "Deal! Welcome aboard, Zoro. Together, we'll take down corruption and achieve our dreams!"

Luffy's nimble fingers worked the blade, swiftly severing the bonds that had held Zoro captive. As the last strand fell away, Zoro flexed his arms, a sense of relief coursing through him.

"Thanks, Luffy," Zoro said, his voice edged with gratitude.

Luffy grinned, clapping Zoro on the back. "No problem! Now we need to find your swords."

Together, the trio made their way through the corridors of the Marine Base. Luffy's keen sense of direction led them to a storage room, where Zoro's three swords were neatly laid against the wall.

Zoro's eyes lit up as he retrieved his prized possessions. "Finally, I've got my swords back."

As Zoro secured his swords, Luffy took a moment to explain his own situation. "Hey, by the way, I was actually here to meet my older brother Ace. We both joined the Marines, and he was supposed to be waiting for me."

Zoro raised an eyebrow, intrigued. "Your brother is in the Marines too?"

Luffy nodded. "Yep! We've got our own reasons, but we're both here to make things right."

Zoro smirked, a hint of respect in his gaze. "Sounds like a plan. Let's put an end to this corruption together."

With their resolve unwavering, Luffy, Zoro, and Koby hastened to the rooftop of the Marine Base. As they emerged onto the open space, they were met with the sight of Captain Morgan himself, standing at the edge of the roof.

Luffy stepped forward, his voice carrying an air of authority. "Captain Morgan, I'm Monkey D. Luffy, a Marine. I'm here to arrest you for corruption and crimes against the people of this town."

Morgan's cold gaze locked onto Luffy, a sinister smile curling his lips. "You've got quite the audacity, boy."

Luffy's grin remained undeterred. "I believe in justice, and I won't let corruption continue under your command."

Morgan's laughter echoed across the rooftop. "Do you honestly think you can challenge me? I am Captain Morgan!"

Luffy's voice remained steady as he addressed the others present. "Listen up, anyone who doesn't want to go down with this corrupt captain, leave now. The choice is yours."

Luffy's resolve blazed like a fire as he faced Captain Morgan, determined to expose the corruption and bring justice to the oppressed town. With a firm stance, he activated his armament haki, imbuing his limbs with a powerful and invisible force. A gleam of determination shone in his eyes as he spoke to Zoro and Koby.

"Watch this, guys. This is why you should join my crew of Marines," Luffy declared.

Without hesitation, Luffy surged forward, his movements fluid and precise. With a swift strike of his arm, he shattered Captain Morgan's infamous "axe hand," rendering it useless. Morgan's expression contorted in shock and pain as his weapon fell to the ground.

Luffy's grin widened, his confidence unshaken. "Is that your best shot? I expected more from the feared Captain Morgan."

Zoro and Koby exchanged impressed glances, clearly recognizing Luffy's skill. Luffy continued his assault, his movements a dance of power and agility. With a flurry of strikes, he evaded Morgan's feeble attempts to retaliate, effortlessly countering each attack. Luffy's fists and kicks found their marks, and soon, Captain Morgan found himself sprawled on the ground, defeated and humiliated.

Luffy stood over Morgan, his tone laced with a mixture of mockery and triumph. "You thought you could oppress this town and get away with it? Not on my watch."

Morgan groaned in defeat, his arrogance shattered. Luffy turned to Zoro and Koby, a playful grin on his face. "See, Zoro? This is the kind of justice we're bringing. And Koby, you can be a part of this too."

Zoro smirked, nodding in approval. "Impressive, Luffy. You've got more skills than I gave you credit for."

Koby was equally amazed, a newfound determination in his eyes. "I want to be a part of this crew, Luffy. Let's bring justice to this town."

Luffy clapped Koby on the back, his grin infectious. "Welcome aboard, both of you. Together, we'll put an end to corruption and make the world a better place."

Author's Note: I hope you found enjoyment in this introductory chapter. While not flawless, it was a pleasure to craft. In this rendition, Luffy's Marine identity takes center stage, his rubber fruit abilities absent but Haki present due to his prior training.