One Piece: Marine Luffy, Garp regrets it

Koala hesitated, her feet seemingly rooted to the ground. Doubt clouded her mind as she considered Luffy's request. Would she—a relative rookie who had only recently mastered both colors of Haki—truly survive a direct confrontation with the Emperor known as the World's Strongest Creature?

Vice Admiral Gion noticed her hesitation and gave her an impatient pat on the back, her voice stern with a hint of challenge.

"Move it, rookie! If you don't join the group effort now, you'll end up facing Kaido one-on-one later."

Without waiting for a response, Gion unsheathed her famous blade, Konpira, from her waist. The legendary sword gleamed in the sunlight as she charged into the battlefield with confident strides.

"H-hey, wait!" Koala called after her. "I'm coming too!"

After quickly weighing her options—fighting Kaido alongside allies versus potentially facing him alone later—Koala made her decision. Group battle was undoubtedly the wiser choice.

However, she still recognized her limitations in direct close-quarters combat against someone of Kaido's caliber. Her Fishman Karate, while formidable against most opponents, might not be enough against an Emperor's overwhelming physical might.

Making a split-second tactical decision, Koala focused her energy and began her transformation. Her body glowed with an ethereal light as she shifted into her human-beast form—the manifestation of her Pink Dragon Mythical Zoan Devil Fruit. While similar in base structure to Kaido's Azure Dragon form, hers was distinctly more feminine in appearance, with rose-colored scales that shimmered like cherry blossoms in spring.

After completing her transformation, Koala maneuvered to position herself strategically. Finding an angle where Kaido was distracted by his engagement with Gion, she inhaled deeply and released a concentrated breath of scorching flame.

"Hmm?"

Sensing the heat wave approaching from behind, Kaido abandoned his match with Gion and delivered a powerful punch toward the Vice Admiral. Gion raised her sword in defense, but the sheer force behind Kaido's blow still sent her sliding back several steps.

The Emperor turned to face this new threat, his eyes narrowing at the familiar technique directed his way. Without hesitation, Kaido opened his massive jaws, gathered his strength, and unleashed his own breath attack—a devastatingly powerful stream of concentrated flame that dwarfed Koala's attempt in both size and intensity.

"Eek! That's too much!" Koala yelped, quickly abandoning her attack and diving sideways to avoid being engulfed by Kaido's overwhelming counter.

As she dodged, her full transformed state became visible to Kaido for the first time. Almost instantly, his eyes widened with intrigue.

"Well, well, little girl," he rumbled, genuine curiosity in his voice. "What's that ability you possess? The Pink Dragon Fruit?"

He paused, reconsidering his assumption. "No, that can't be right. There shouldn't be two identical Devil Fruits existing simultaneously in this world."

His eyes gleamed with increasing interest as he studied her form more carefully. "Your coloration differs from mine... could it be a sister fruit to my Azure Dragon? A complementary power?"

A wide, unsettling grin spread across his face. "Oh ho ho ho! This becomes more fascinating by the moment!"

Kaido's self-directed musings ended with boisterous laughter that echoed across the battlefield. The sound sent chills down Koala's spine, causing her to tremble involuntarily like a cornered animal. Just now, she had felt a primal fear—the terrifying sensation of being marked as prey by an apex predator.

There's no doubt about it, she thought with growing panic. He's fixated on my Devil Fruit. He wants to see its full capabilities...

Koala's thoughts raced frantically. What should I do? What should I do?! I've barely joined the fight and already I'm being targeted by the final boss! Hancock-san! Gion-san! Yamato! Someone help me!

But contrary to her internal pleas, the situation was developing more favorably than she realized. While Kaido stood laughing and momentarily distracted by his discovery, the three female warriors had already prepared their coordinated assault.

Seeing that Kaido had foolishly turned his back to her, Vice Admiral Gion's eyes flashed with fierce determination. She gripped Konpira's hilt tightly with both hands, dropped into a low stance to gather momentum, and adjusted her grip so the blade was positioned horizontally, aimed directly at Kaido's exposed back.

"Ittoryu: RANKAKYU!" she shouted, her voice cutting through the air like her blade soon would.

As power accumulated in her limbs, Gion pushed off with explosive force, launching herself forward with blinding speed.

Though Kaido's attention had been captured by Koala's transformation, his battle instincts remained razor-sharp. Sensing the imminent danger approaching from behind, he snapped back to awareness and swiftly pivoted, raising his kanabo to intercept Gion's strike.

Simultaneously, he began gathering energy in his throat, preparing to unleash another devastating breath attack at the first opportunity.

But someone moved even faster than the Emperor.

Just as Kaido's fiery breath began to take form, Yamato's icy counterattack struck first. Her "Namuji Hyoga" hit him square in the face, the sudden temperature shock disrupting his technique before it could fully manifest.

Capitalizing on this opening, Hancock followed with perfect timing. She launched herself into the air with graceful precision, her long legs—now coated in the glossy black of Armament Haki—connecting solidly with Kaido's midsection in a devastating kick.

More dangerous than the physical impact was the special property imbued in her attack. Where her leg made contact with Kaido's body, the skin began to show the telltale signs of petrification—slowly turning to stone from her Mero Mero no Mi ability.

Witnessing the three women's coordinated assault successfully delay Kaido, Koala couldn't help but exhale in relief. But that moment of respite quickly gave way to shame as she reflected on her own performance.

I allowed myself to be intimidated by Kaido's mere presence, she thought, her face flushing with embarrassment. What kind of revolutionary am I? If I cower before Kaido, how can I ever stand alongside Luffy against the World Government?

The reality of her situation struck her forcefully. Luffy had brought only four combatants on this mission apart from the observers Mansherry and Viola. Now Yamato, Hancock, and Gion were engaging Kaido head-on, holding their own through teamwork and coordination.

Meanwhile, she had contributed nothing but hesitation and fear.

I possess the same class of Devil Fruit as Kaido—a Mythical Zoan Fish-Fish Fruit, she realized. So why is he so overwhelmingly powerful while I shrink away at the first sign of danger?

In that moment of clarity, something profound shifted within Koala's mind and heart. She was no longer the helpless slave child of the Celestial Dragons, bearing their mark and living in constant terror.

Nor was she merely a low-ranking Revolutionary soldier, relegated to support roles while others took the spotlight.

She was Koala—user of a rare and powerful Mythical Zoan Devil Fruit, Deputy Director of Intelligence for Marine Branch G66, and a woman destined to stand beside the future Pirate King!

"KAIDO!" she roared, her voice carrying a newfound strength that surprised even herself. "Stop acting so high and mighty! I'll show you just what I'm capable of!"

The four paused their skirmish momentarily, all turning with varying expressions of surprise to witness Koala's transformation—not just physical, but spiritual. The timid rookie was gone, replaced by a warrior with blazing determination in her eyes as she strode purposefully toward them.

Though Kaido couldn't understand what had triggered this sudden change in the young woman, he couldn't help but smile with genuine excitement. Brushing off the attacks from the three women as if they were merely an inconvenience, he hefted his massive kanabo onto his shoulder, his eyes locked on Koala's approaching form.

"Wororororo~" his distinctive laugh echoed across the battlefield. "That's the spirit! All that confidence... now let's see if you have the strength to back it up!"

His eyes gleamed with dangerous anticipation. "Come then, little dragon. Let me test your limits!"