An Oni in God's Valley

In the Year 1480, on an island known as God Valley, named for its vast natural resources and mythical reputation, a young boy wandered alone through the dense forest. He was holding a weathered, partially torn piece of parchment in his small hand, his sharp eyes scanning the terrain as he walked with surprising confidence.

The child's name was Maui D. Koa, only five years old, but with a stature that could easily be mistaken for a child twice his age. His appearance was both mesmerizing and eerie—white hair, red eyes, and two dark colored horns protruding from his head. Though he bore features of the mysterious Lunarian race, he lacked the typical black wings and the fire that usually burned at their backs. His physique suggested strength far beyond what a child should possess—perhaps a hint of his Oni lineage.

Clutched in his hand was an old map, something he had found buried beneath the floorboards of a ruined cabin on the western cliffs. According to the markings, a hidden treasure chest lay somewhere in the forest, near a formation of twisted trees resembling a crude spiral.

Following the map's path, Koa came to a stop. The trees here curled unnaturally toward each other, just as the drawing had shown. His crimson eyes scanned the area carefully until he noticed a suspicious bush, its leaves darker and denser than the ones around it. With a grin creeping onto his face, he knelt and began digging beneath the bush.

Sure enough, his hands struck wood—a buried treasure chest, its metal bindings rusted but intact. He pried it open, revealing a pile of aged gold coins and trinkets... but resting at the top, like a crown atop treasure, was an oddly patterned fruit. Its spiral ridges and deep purple skin marked it unmistakably as a Devil Fruit.

Koa stared at it, his grin widening.

"Jackpot," he muttered under his breath, lifting the fruit and examining it. He then took out and flipped through the Devil Fruit encyclopedia he had until he reached the page where the exact picture of the model was, and there he learned the name of the Devil Fruit.

Wapu Wapu no Mi.

A flicker of recognition passed through Koa's eyes. "The Warp-Warp Fruit, huh… Isn't this the Devil Fruit of Van Augur in the future, hehehehe lucky"

He looked down at the chest, then around at the quiet forest.

"I hope whoever buried this is long dead," he muttered with a chuckle, slipping the Devil Fruit into his travel sack along with a handful of coins. "Otherwise, I might owe someone... and I hate owing people."

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It had been about a year since Koa was transported into the world of One Piece. He had just discovered his first natural Devil Fruit—aside from the one he had personally designed through a survey: the Hito Hito no Mi, Model: Ruaumoko.

In that survey, he had created an original character who bore the Will of D., a hybrid of Lunarian and Oni lineage, similar to Kaido's bloodline. However, unlike typical Lunarians, Koa had sacrificed his race's signature fire generation and wings in exchange for enhanced physical attributes: immense durability, overwhelming strength, and incredible speed. His body had grown so resilient that even Kaido and Big Mom's natural defenses were considered inferior by comparison.

On top of that, Koa had integrated the Scopper Gaban template into his being, which amplified his innate talent in all forms of Haki. The template granted him Gaban's combat instincts and martial arts proficiency, stacking on top of his already prodigious natural ability.

To assist him on his journey through this dangerous new world, Koa was also equipped with several powerful tools. He possessed three enchanted talismans—Dog, Snake, and Rooster—each functioning like Devil Fruits with stamina-based drawbacks. Additionally, he wielded a unique weapon: the Labrys of the Abyss, a massive double-headed axe inspired by Asterios from the Fate series, perfectly suited for his growing strength and brutal combat style.

Fortunately, the Ruaumoko model fruit he created was immune to both seawater and Seastone, a deliberate and crucial design choice. Without that immunity, basic survival—let alone hunting—on such a wild and untamed island would have been nearly impossible.

Ever since discovering he had landed on God Valley, a land drenched in history and blood, Koa had trained relentlessly. A full year of solitude, survival, and discipline had stripped away any remnants of weakness. He was no longer a confused boy lost in a foreign world.

"I'll just have to push my training even further—to make sure I don't die when the real chaos begins. And once it does… I'll be there to collect the treasures those arrogant Celestials are hoarding," Koa thought, a grin curling on his lips. "Hehehe… I'm drooling just thinking about it. And I'll help Ginny, Kuma, and Ivankov too… they've already suffered enough."

With that, he activated one of his talismans—the Snake Talisman—and his form shimmered out of sight. His travel bag, now filled with a Devil Fruit and a stash of gold coins, vanished along with him.

Cautious by nature and wise beyond his years, Koa had already chosen to remain isolated from the other residents of God Valley. As a Lunarian hybrid, he was acutely aware of the persecution his kind faced in this world. He wasn't about to gamble on the goodwill of strangers—if they discovered his identity, they might sell him out to the Marines, condemning him to a life of slavery.

And so, in silence and shadow, Koa moved through the forest—unseen, unknown, and unyielding. Every day was a step closer to the storm.