One Piece: sign-in to Ryujin Jakka

Roman had yet to begin formally teaching Ain the full scope of swordsmanship.

All he had done was instruct her to lay the foundation. Training her body, honing her will, and tempering her mental state through various diverse experiences.

Now, Ain's state of mind had reached an extraordinary calmness.

Facing Vander Decken IX, her heart remained still; no waves, no panic.

A profound serenity enveloped her, allowing her focus to reach new heights.

Alongside it, her reaction speed and combat capability subtly surged.

"You don't know? The faster you run, the faster you die!"

Vander Decken IX sneered as he charged toward her.

Seeing this, Shirahoshi's heart instantly clenched.

"Be careful! Don't let him—"

Before she could finish, Roman stopped her.

"Shirahoshi, this is Ain's fight," Roman said seriously.

"She needs to observe her enemy's abilities, analyze the situation, and defeat him on her own. So for now… don't warn her and interfere ."

Shirahoshi paused, then slowly nodded, understanding Roman's intent.

She had been about to warn Ain not to let Vander Decken touch her.

Because once he did, the power of the Mark-Mark Fruit would activate, and his attacks would never miss, guaranteeing a perfect hit every time!

Right now, Ain clearly didn't know about this trait.

But her swordmaster instincts were in full effect.

She pushed her peak-level swordsmanship to its limit.

Her aura was like a drawn blade—sharp, focused, deadly.

Ain gripped her blade, twisted her wrist, and unleashed a swift, sharp strike that roared toward Vander Decken IX.

But the man wasn't entirely incompetent.

Just barely, he dodged her slash and managed to graze the hem of her clothes.

Vander Decken's lips curled in a sinister grin.

From seemingly nowhere, he pulled out eight throwing knives—four in each hand.

The blades were laced with venom, glowing a ghastly green that sent chills down the spine..

"Bahahaha! You're already as good as dead now! I'm the cursed user of the Mark-Mark Fruit! Anything I touch becomes my guaranteed target! So—go to hell!"

With a mad laugh, he flung the knives into the air.

They shrieked through the sky, cutting toward Ain with venomous promise.

Ain furrowed her brow, but her heart stayed calm.

"Slash!"

With one swing, she unleashed a powerful sword strike, infused with all her understanding at the peak of swordsmanship.

A hurricane of sword aura erupted outward.

A sharp arc of energy sliced through the air, as if splitting the very atmosphere itself.

Screeeeech—!

A cloud of debris exploded where the blade passed.

Roman's eyes lit up as he watched.

"Good! Stay in that state! Use this battle to break into the realm of the Great Swordmaster!"

"Yes!"

Ain shouted in response.

The venomous knives met her devastating slash—

Clang! Clang! Clang!

Each one shattered in midair, cleaved clean in two, and fell harmlessly to the ground.

Now!

Ain's beautiful eyes narrowed.

"Shave!"

Her figure blurred and vanished, appearing instantly behind Vander Decken IX.

"Return-Return Fruit ability—activate."

Ain wasn't just a peak swordswoman.

She was also the wielder of the Return-Return Fruit—a Return Human.

Anyone or anything she touched could be reverted to their state twelve years in the past.

And the more she trained the fruit, the greater the time reversal would become.

At its peak… even a single thought could erase someone from existence.

Vander Decken IX suddenly felt his body shrinking.

His oversized clothes hung loosely on his now frail, youthful frame, awkwardly mismatched.

Ain's momentum had reached its peak. A brilliant gleam flashed in her eyes.All of her recent insights, every realization she had while following Roman, clicked into place at this moment.

Her aura surged tenfold. A terrifying sword intent erupted, expanding like a tsunami from her center.

Around her, seaweed on the seafloor was blown into a frenzy by the swirling wind.

"This… this is the realm of the Great Swordmaster?!"

Feeling the immense power flowing within her, Ain's blood boiled with exhilaration!

Shock! Awe! Terror!

Vander Decken IX's heart pounded with dread.

Moments ago, they had been evenly matched. Now, in a mere breath's time, everything had changed. His strength, speed, and reflexes were rapidly fading.

Meanwhile, Ain's power had grown tenfold. There was no way to win now!

A crushing sense of doom wrapped around him like a cold shroud, plunging his heart into despair.

Ain swung her blade again and again. Each strike sent dazzling waves of sword energy slashing through the air, piercing straight toward Vander Decken. Her aura was like a tidal wave! And each swing further solidified her footing in this new realm.

Boom! Boom! Boom!

The air itself tore apart. The seafloor cracked and trembled beneath them. Violent gales howled through the battlefield. Under the relentless onslaught, Vander Decken IX could only watch in horror.

"Breaking through in the middle of battle… this isn't fair!!"

"Damn it, even just her aura… I can feel how powerful these slashes are!"

"No! I can't dodge this!"

A storm of thoughts raced through his mind.

In the end, they all led to one conclusion:

He was going to die.

"Damn it! If I'm dying, you're all coming with me!!"

Before the final strike landed, Vander Decken reached out—

And touched Noah's Ark.

Mark-Mark Fruit ability: activated!

The massive ancient ship suddenly stirred, like a beast awakened from its slumber.

Sea currents roared as it began to float upward, rising with unstoppable momentum before suddenly plunging down, straight at Ain!

At the same moment, dozens of slashes finally cut through Vander Decken IX, ending his life.

But the danger wasn't over.

A new crisis had begun!

Ain looked up at the gigantic Noah's Ark bearing down from above.

She instinctively gulped.

Cold sweat appeared on her brow.

She could already imagine the devastation that would follow once that enormous ship came crashing down.

It could likely destroy all of Fishman Island in one blow!

To fishmen and merfolk, a disaster like this might be survivable in the deep sea.

But for humans—especially Devil Fruit users—it was a death sentence!

Especially for those like them, who could never swim…

"I have to do something!"

Ain, who had just broken into the realm of the Great Swordmaster, could feel no joy.

Only grim determination.

She took a deep breath, her face solemn.

She had made up her mind—

If it meant sacrificing herself…

Then so be it.

Maybe that would be enough to stop Noah's Ark.