Uchiha Puppet Master, Starting from One Piece

(I should clarify that, with the system's help, the Mangekyou Sharingan opens up different timelines in each world.)

At dawn, as the first rays of sunlight pierce through the morning mist and spill onto the shimmering sea, golden light sparkles like shattered diamonds. Flocks of seagulls follow the boat, emitting clear cries.

When the sea breeze, carrying a salty and damp scent, brushes against your cheeks, as gentle as a lover's hand, it curls your hair and your skirt.

Daytime always passes by exceptionally well.

Robin was busy studying the nautical charts. She recorded the features of the sea areas along the way. The reefs hidden in the ocean currents and the small islands suitable for temporary docking were all clearly marked by her. In the absence of a navigator, Robin was a very reliable navigator.

As evening fell, everyone would gather around the deck, light a bonfire, and grill fragrant meats and squid. Matsumoto Rangiku would bring out her treasured sake and drink with Shiraha, the sake carrying a rich aroma as it went down her throat. Connor would snuggle up to Robin, munching on grilled meat while listening to Robin recount her past of hiding and running away.

The waves crashed against the hull of the boat, and the campfire flickered, casting a red glow on everyone's faces. The puppets stood quietly by, some adding firewood, others grilling fish, their movements practiced and skillful, a testament to Uchiha Hakuba's excellent training.

Such days are peaceful and warm, with other dangers kept at bay in this calm and sunny sea.

Seven days passed in the blink of an eye, and everything went so smoothly.

On the seventh night, the moon was bright and the stars were few.

Silver moonlight poured down like flowing water, covering the entire sea surface, shimmering and beautiful as a dream.

The campfire on the deck had long since died out; only the chirping of insects and the sound of the waves mingled together, creating a tranquil and peaceful atmosphere.

Connor was nestled in Robin's arms, fast asleep, a trace of barbecue oil still clinging to the corner of his mouth.

Matsumoto Rangiku leaned against the mast, a sake jar beside her, her breathing even; she was clearly fast asleep.

The puppets stood quietly in every corner of the ship, like loyal guards.

Bai Yu stood alone at the bow of the ship, the sea breeze ruffling his black hair and causing his clothes to flutter.

He looked up at the night sky, a faint crimson light flickering in his deep eyes.

The seven days of peaceful sailing not only allowed the ship to approach Europa Town smoothly, but also restored his chakra and mental strength to an unprecedented peak.

He was ready to summon new companions. Although he felt his eyesight was deteriorating, he wasn't too worried because the progress bar of his cheat ability was constantly rising.

……

Outside the courtyard of the Fourth Division, fallen maple leaves carpeted the ground in red.

Unohana Retsu paused in her hand, which was holding the medicine box, and laid out the herbs she had recently picked to dry.

Even with the ability to return to one's original path and her Zanpakuto, she sometimes still needs the assistance of medicinal herbs, since her teammates are not her and do not have her ability to return to one's original path.

At the same time, five asahi-tatami swords were laid out in front of her; these were to be given to the students of the Shinigami Academy the next day.

She looked down at her hands, hands that had once held the sharpest sword in Soul Society, and five hundred years later had become the hands of a doctor, using the Reidou to heal others.

From Unohana Yachiru to Unohana Retsu, from the most feared villain in Soul Society to the captain of the Fourth Division, time flowed like a silent river, washing over her blade and the bloodlust in her eyes.

Five hundred years ago, in the Soul Society, there was no Gotei 13.

There was no order from the Gotei 13, only the wilderness of Rukongai, and countless Zanpakuto thirsting for blood.

At that time, she wasn't called Yachiru yet.

At that time, the Zanpakuto, Minashizuki, at her waist was not a weapon for healing others.

Back then, it was a weapon whose swift, chilling winds carried with it, capable of killing without hesitation.

She challenged every swordsman in Soul Society. Those who could split boulders and shatter steel couldn't even last a single move against her. Her sword was too fast; so fast that her opponents only saw a blur before warm blood splattered from their necks.

She also challenged the noble scions of Soul Society. Those self-proclaimed nobles, wielding Zanpakuto, were like children in front of her, crying and begging for mercy. She didn't even flinch; with a single slash of her blade, a life was ended.

This does not include the five noble families, of course.

Her name was forged in blood.

The name "Yachiryū" refers to the eight thousand styles of swordsmanship. Every opponent who fell to her sword was once a master swordsman with their own unique skills.

She dissected and assimilated the techniques of various schools of swordsmanship, ultimately transforming them into her own unique way of swordsmanship.

At that time, she was a warrior, and no one could stop her when her sword was pointed at her.

She stood for three days and three nights amidst the mountains of corpses and seas of blood in Rukongai. Beneath her feet lay countless corpses, and beside her lay mountains of corpses and seas of blood. In that era of the survival of the fittest, pity was the most useless thing.

She remembered that her knife was always stained with blood that could never be washed away.

"Yachiru! You heartless killer!"

Someone was cursing behind her, but she simply turned around, and with a flick of her blade, the cursing stopped abruptly.

How many people did she kill?

One thousand? Two thousand? Or several thousand?

She couldn't remember.

All I know is that the sky was always stained red with blood back then, and all I know is that my eyes were filled with the fervor of battle, without the slightest ripple of emotion.

Until that person appeared, the one who made her give up the sword and turn back to the Way.

The person who made her feel both the joy and pain of fighting appeared...

After that, looking at her blood-stained hands, she suddenly felt a little tired.

After that day, the name Unohana Yachiru disappeared from the history of Soul Society.

Instead, the captain of the Fourth Division, Retsu Unohana, took his place.

She began learning medicine from Kirinji Tenjiro, from identifying herbs to suturing wounds, from preparing medicines to healing serious injuries.

The Nijizuku also changed its appearance, transforming from a sharp longsword into a healing sword that resembled butterfly wings.

But her pantheon...

Five hundred years have passed slowly like this.

After going to the Soul King Palace at Kirinji Temple, she became the best doctor in Soul Society, and under her leadership, the Fourth Division became the most popular division among the Gotei 13.

Those wounded Death Gods rose again under her healing, and watched those dying souls be reborn under her guidance.

However, occasionally, in the quiet of the night, she would stroke the hilt of the flesh-crushing sword and recall the self who once wielded the sword amidst mountains of corpses and seas of blood.

I recall the sound of a blade slicing through the air, the warmth of blood splattering on my face, and the frenzy of the battle.

Five hundred years of peace, like a thin layer of ice, covered the flames in her heart.

She began to feel somewhat bored.

Tired of the monotonous days, tired of this calm and uneventful life.

She still longed to wield her sword against those who committed evil, and against those powerful individuals.

Just as I was thinking this, suddenly, a strange power came from the void.

It was a kind of... indescribable calling.

It wasn't spiritual pressure, nor was it the power of a Kido, nor was it the power of a Zanpakuto.

That power was peculiar, carrying a spatial distortion-like fluctuation.

She frowned, raised her head, and looked up at the sky.

Suddenly, a crack appeared in the void. The crack was small, but it emitted a faint light, and something on the other side seemed to be attracting her.

A not-so-strong suction force came from the gap.

She didn't resist; she simply let the suction force pull her in, carrying her Zanpakuto and the Asauchi she was about to unleash...

"Anyway, with that guy Yamamoto around, Soul Society can stay peaceful forever..."

A long-lost smile appeared on her lips.

She could sense that there was someone on the other side of the gap.

Uchiha Hakuha.

The name inexplicably surfaced in her mind.