[D Experiment Subject]:
Under the guidance of scientist Vegapunk, the Vinsmoke family secretly conducted years of research into what was known as the "D Experiment."
By a twist of fate, only one successful case ever emerged.
Yes, Sanji was an experiment.
Luffy had known that much for quite some time.
Though it sounded tragic, Sanji truly was nothing more than a product, a being artificially created through the power of science within his own family.
What truly shocked Luffy, however, was that Sanji was the only successful subject!
In his memory, Sanji's father, the King of Germa 66 and head of the Vinsmoke family, Vinsmoke Judge, had always called him a failed, useless specimen.
At the time, the news had left Luffy stunned. He immediately asked the system:
"What is the D Experiment?"
Yet, the system's answer was cold and mechanical:
[This system cannot respond to questions beyond attribute descriptions.]
In the end, Luffy learned nothing more.
The only successful case of the D Experiment…
In the anime, it was merely mentioned that Sanji and his siblings were created through lineage factors, but it was never explained exactly what kind of lineage factor.
Now, however, the answer was becoming clear.
[D]
That single letter appeared vividly in Luffy's mind, sending him deep into thought.
In the pirate world, the letter D had always been a symbol of mystery.
No one knew what it truly represented, or if anyone did, no one was willing to speak the truth.
If not for the system's reminder, Luffy might have already forgotten that there was still such an unsolved enigma lurking in the world of pirates.
What he didn't expect, however, was that his first real encounter with the mystery of D would come through Sanji.
If the system hadn't listed it separately, Luffy might never have known about the secret hidden within Sanji's body.
Imu, the Celestial Dragons, Roger, Vegapunk, D, secret experiments…
Everything was a riddle wrapped in another riddle.
The more I learn… the more I realize how much I don't know.
Luffy couldn't help but grin. The world was still full of fascinating things worth looking forward to.
"Looks like I've gotta step up my training again," he said with a confident, carefree smile. "I've been slacking off lately!"
Ever since realizing that his power was enough to take on an Admiral, Luffy hadn't really pushed himself to grow stronger.
His days had been filled with eating, playing, and basking in the benefits of his crewmates' growth.
Now, even the Going Merry had a training room, one with special properties that allowed fighters to spar freely without damaging the ship itself.
Zoro had been sparring with Koby day after day… he was probably getting bored, right?
Time to stretch these muscles a little.
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"System! Draw Sanji's exclusive item!"
The world was becoming more and more interesting…
For the first time, Luffy found himself eager, truly eager, to enter the Grand Line, and eventually the New World.
He wanted to uncover all those tiny hidden secrets, the ones the world's powers had buried so deep that not even history itself dared whisper them.
Who was hiding the truth?
Who was digging it back up?
Ohara, the country erased from the history books, what kind of secret did it hold that the World Government would rather burn it to ashes than let the world know?
Surely, there were at least two or more powerful forces secretly contending for control over this world.
And Gol D. Roger, the former Pirate King… how much truth had he uncovered?
Why did he choose not to tell the world, but instead surrender himself to the Marines?
What role did he play in all of this?
And what did One Piece truly conceal?
All these mysteries scattered across the seas… only Luffy himself could uncover them, piece by piece.
But for now, he should focus on the task at hand.
With a whoosh, a massive wheel of fortune appeared before him at his command.
Without even needing his touch, the wheel spun wildly, blurring with countless strange and fantastical items flashing past.
When Luffy lifted his head, the system had already chosen Sanji's exclusive item.
[Congratulations, host. You've obtained: "Gourmet Cell Modification." The item has been placed in your inventory. Please check.]
"Huh? Gourmet Cells?!"
Luffy opened his inventory curiously, only to find everything looking the same as before, no new items in sight.
Having learned from Koby's earlier "Nen" incident, Luffy focused his willpower on the final empty slot in his inventory.
Sure enough, a new info window popped up:
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[Gourmet Cell Modification]
Origin:Toriko World
Effect: Converts all of the user's body cells into Gourmet Cells.
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Just a few simple lines of description.
"Gourmet Cells…"
Luffy rubbed his chin thoughtfully.
He didn't know much about this ability, mainly because he'd never watched Toriko.
All he knew came from the One Piece × Toriko crossover movie and a few novels he'd skimmed long ago.
From what he remembered, Gourmet Cells allowed one to grow stronger simply by eating, and the better the food, the stronger they became.
An ability with no upper limit.
Powerful indeed… yet Luffy couldn't help but feel something was off.
"Wait… doesn't this totally not suit Sanji?!"
He was a chef, for crying out loud! If Sanji started eating all the good food himself, what would the rest of the Starry Sky Pirates eat?
And surely the others wouldn't fight him for it, how could they stop their cook from getting stronger?
Sighing, Luffy said helplessly, "System… didn't you say the exclusive items drawn are always highly compatible with their users?"
"This Gourmet Cell thing, anyone could use it, right? Doesn't seem all that fitting for Sanji."
He paused, a spark of regret flashing in his eyes.
"I did see you had a Kamen Rider transformation belt earlier! How about we trade, huh?"
Kamen Rider!
Luffy didn't even know which Rider it was, but surely that had to be better than a food-obsessed chef, right?!
Gourmet Cells might have infinite potential, but that potential required endless accumulation.
Kamen Riders, on the other hand, gained immense power the instant they transformed.
Some could even teleport, or manipulate time itself!
But his plea was in vain.
[Exclusive partner item draws cannot be changed.]
[Additional note: Compatibility between Sanji and the Gourmet Cell Modification exceeds 99.99%.]
The system's cold voice left no room for argument.
"Ninety-nine point ninety-nine percent? You've gotta be kidding me," Luffy muttered, rolling his eyes.
Still, he couldn't completely ignore it.
The system wouldn't lie, not about something like this.
If even it praised the Gourmet Cells so highly, then perhaps there was more to them than he realized.
Well… I'll find out tomorrow.
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Night fell quietly.
Through the round porthole of the cabin, a pale beam of moonlight filtered in, stretching across the floor like a silver ribbon.
It felt almost as if the moon itself were whispering secrets to Luffy…
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Notes: Toriko World – A reference to Toriko, another manga/anime series where characters possess "Gourmet Cells," granting them incredible strength through consuming powerful foods.