One Piece: Navy Traitor, I Marry the Female Emperor To Rule the Sea

Ding! Quest triggered!

Option 1: Strike down Vander Decken IX with thunder, rescue Mermaid Princess Shirahoshi, and shock everyone on the scene! Reward: Divine Transformation Potion X1 (transforms a mermaid into human form and size), with a bonus: Shirahoshi's favor!

Option 2: Ignore Vander Decken IX, confront King Neptune about why Shirahoshi wasn't there to greet you, then after establishing your dominance on Fish-Man Island, go to rescue Shirahoshi. Reward: Skill: Intermediate Sea King Control (can control small to medium-sized Sea Kings, ineffective on giant ones).

As Shiro looked up at the beautiful and enormous Mermaid Princess being abducted, his mind was already made up. A mere Fish-Man Island, something that even Jinbe could handle without the need for drastic measures.

From Shiro's perspective, most of the residents of Fish-Man Island, aside from troublemakers like Arlong and Hody, were generally kind-hearted and part of a marginalized group in the world of pirates. It was clear that they weren't like the ruthless pirate nations.

Moreover, how could Shiro stand idly by while the enormous and innocent Shirahoshi was being taken away by the vile Vander Decken IX? That scoundrel wasn't worthy!

"Why are you just standing there? Go save Shirahoshi!" Neptune shouted, his face twisted with desperation. "You guys, hurry and find Jinbe to rescue Shirahoshi!"

Despite his concern, Neptune instinctively called out to his sons and Jinbe rather than Shiro. Even though Shiro was undeniably powerful, the people of Fish-Man Island were still unfamiliar with him.

Just then, a deafening rumble echoed through the Ryugu Kingdom before Neptune could even finish his plea. A thunderous roar filled the air, and the eyes of the Fish-Man Island residents turned towards Shiro.

With a simple wave of Shiro's hand, a terrifying thunder dragon shot forth, its destructive force barreling towards Vander Decken's pirate ship in the sky!

The crowd gasped in astonishment! Even Neptune, a seasoned ruler, quickly realized that the sheer might of Shiro's attack meant certain doom for Vander Decken. But his daughter Shirahoshi was on that ship too! If that thunder dragon struck, she might be turned into a charred mermaid!

The moment of panic came to a halt when the thunder dragon struck. The enormous ship disintegrated under the overwhelming power of Shiro's lightning. Yet, miraculously, the lightning deftly avoided Shirahoshi's delicate figure, creating a safe zone around her.

Vander Decken IX, on the other hand, was not so fortunate. Before he could even react, he was turned to ash by the millions of volts of electricity. There was no resistance—only instant obliteration.

This display of Shiro's power stunned the entire crowd. The residents of Fish-Man Island looked at him with newfound awe and respect. Even those who had doubted Fish-Man Island's inclusion in the Central Authority's sphere of influence began to change their views.

Shiro's actions weren't just powerful, they revealed his sense of justice and restraint.

"Shirahoshi is falling!" Neptune screamed in panic as his daughter began to descend from the sky. Her immense size made the fall potentially catastrophic. But just as Neptune was searching for a solution, Shiro ascended effortlessly into the air.

Ding! Congratulations, host, on completing the quest. Reward: Divine Transformation Potion X1.

Appearing right in front of the enormous Shirahoshi, Shiro reassured her, '"Shirahoshi, open your eyes. You're safe, you won't get hurt!"

Shirahoshi, eyes wide with surprise and fear, looked at the man who had saved her.

"You… who are you?" she asked, her voice trembling.

"I'm Shiro," he replied with a calm smile, not saying much more. He took out the potion from his system space and gave it to Shirahoshi without hesitation.

"What did you just give me?" Shirahoshi asked innocently, staring at him with wide eyes.

In mere moments, her body began to shrink, transforming into a normal human size, albeit still smaller than Shiro. This miraculous transformation left everyone around, including Neptune, in utter amazement.

Shiro's strength and mercy had not only saved Shirahoshi but also won over the hearts of the people of Fish-Man Island. At Neptune's invitation, Shiro joined the grand feast held in his honor. As their most distinguished guest, Shirahoshi accompanied him, clearly enamored with her savior.

From a distance, Robin observed the scene with a hint of amusement, knowing that the number of rivals for Shiro's attention was growing. She mused to herself, "I should bring Nami over soon. At this rate, Shiro might conquer the New World before the Straw Hat Pirates even get the chance!"

As the feast carried on, the political landscape of Fish-Man Island was beginning to shift in response to Shiro's heroics.

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The fanfic is finished on p@treon/tambeerg