Chapter 90: Mad Genius

"──Someone stop heeeeeeeeeeer!!!"

"UwaaaAAAAHHH!?"

The Beast Pirates' stronghold—Onigashima—was in chaos.

From the outer residences of the Tobiroppo to the agricultural production zones, even deep inside the live floor, crewmembers were being sent flying one after another as the rampage continued. If this were an intruder, they’d eagerly raise their weapons in the name of the "Emperor" Kaido to deliver the baptism of the New World. But given who the culprit was, they could only grimace in frustration.

"Hey, where’d she go!?"

"Find her!! If we don’t hurry, who knows what she’ll—!!"

"Owowow… Damn, that was close. Almost got slashed."

Even the burliest, roughest crewmembers wore sour expressions as they scoured the area. Slash marks littered the walls and floors, and some had already been struck—blunt side or not—by a blade. Only one person could cause this much havoc and still be untouchable. The crew cried out in unison:

"Lord Musashiii!! Where are youuu!?"

"Please, stop wrecking things and come out!!"

"Kaido’s looking for you!! You’re gonna get chewed out again!!"

"──Fuhaha."

──And there, perched atop the overlapping ceiling beams, a single figure watched them.

Dressed in a black hooded coat (only fastened at the chest), white shorts, and black boots, the small-framed girl had short black hair—save for one long red strand hanging from the side. In the shadows, the upside-down cross on her chest and the chains draped over her shoulders glinted faintly. Those chains held her twin swords.

But her most striking feature? The two horns sprouting from her head.

"Fools. You think you can capture me? The only one who could possibly— Hm?"

The girl—barely 150 cm tall—grinned down at the chaos below until something flickered across her expression.

"The old men are coming… Time to bolt."

She stood, ready to vanish. She could already sense those sent to catch her.

"Fuhaha, hide-and-seek it is… Now, what’s the phrase again…? Ah, right!! 'Catch me if you caaaaan!' Fuhahahaha!!"

Though no one heard her, she declared it anyway before shapeshifting into a beast and leaping away.

---

Meanwhile, from the underground floor, I tracked her presence.

"She’s wrecking the agricultural zone!!"

"What the hell’s Musashi doing now!?"

"Hah!? That brat’s messing up MY farm!?"

Guided by reports, Kaido, Nue and the others stormed toward the scene. As they fumed, I updated them:

"──She’s moved… Now she’s on the live floor."

"The hell!? She’s trying to escape again!?"

"No clue!! She’s just rampaging, demanding to see you, Lord Kaido…!!"

"Tch… Hey, King!!"

"!"

Kaido clicked his tongue and barked orders. King immediately pulled out a Den Den Mushi—Sumashi—to coordinate.

"Cut her off!! She’ll bolt the second she senses us coming!"

"Understood… But Kaido, she’s using Observation Haki to track us."

"I know!! That’s why you follow Nue’s directions through the Sumashi!!"

"Got it."

As King relayed commands, I perched on Kaido’s shoulder and directed the others.

"If she’s on the live floor, block all exits. The sky will be handled by King and my UFO... Queen, take the front. Jack, the back. Ulti, seal the side exit with the others!"

"Roger!!"

"Then Kaido and I will head straight to the live floor. If anything happens, contact me via Escargophones!!"

"YES, MA’AM!"

"That damn Musashi~~!! Today's the day I split her skull wide open!!"

With the entire crew mobilized—Tobiroppo, All-Stars, and all—the hunt for one child began. Overkill? Maybe. But with Musashi, it was necessary.

"Sigh… How many times has she slipped past you now? Weren’t you supposed to be watching her? I heard she came back from her ‘street-slashing’ and was behaving today."

"Our deepest apologies!!"

"We tried stopping her, but Lord Musashi’s strength is…! There was no way—"

The bandaged guards trembled. Well, they weren’t wrong. Musashi’s raw power made containment impossible. Should I praise her or scold them? Deciding to table it, I turned to Kaido.

"So, how are we disciplining her this time? Beatdown?"

"Damn right!! A thrashing and no food for a while!!"

"Ten days, then. A couple won’t teach her anything."

(That’s not discipline—that’s torture!!)

(This family’s messed up as usual…)

Huh? The crew’s making weird faces… Eh, whatever. Priorities.

"Well, at least we’re here now. Without me, catching her’d be a nightmare."

"That brat’s born with insane Observation Haki…! Add her idiocy and daily rampages…! Yamato’s the same—why’d they turn out this stupid!?"

"Wanna sign up for Linlin’s Perfect Parenting Classes?"

"Like hell I’m going to that hag’s!!"

"'Ha~hahama-mama!! Linlin’s Parenting Class…!! Starting now…!! Aim to be an Emperor like meee~'—"

"!!!?"

"Quit shapeshifting!!"

"Aw, you saw through me instantly."

(M-my heart almost stopped…!!)

My flawless Big Mom impression made the crew jump, but Kaido wasn’t fooled.

"Quit screwing around. Let’s go."

"Right, right.—Hm?"

As I refocused my Observation Haki, another presence flickered into view.

"Hey, what’s up?"

"Hmm… Yamato’s heading toward the live floor."

"The hell!? Speak faster!!"

"Gimme a break. I can’t monitor everything at once— Oh."

"Now what!?"

"Pretty sure Yamato just knocked out Page One… And now Musashi’s going wild again."

"Hah!?"

Is Musashi trying to draw attention with this timing? I see. Her innate Observation Haki surpasses mine in sensing presences—she must’ve detected Yamato’s and acted accordingly.

Which means… her target might be Hiyori? If Yamato’s involved, the motive fits. Musashi would absolutely take interest if she learned her identity.

But even so. It’s too late for Hiyori to back out now, and this is a perfect opportunity. Maybe I’ll let them stir the pot a little longer—see what happens.

---

──To face the unexpected without faltering.

Or, if you do falter, to regain composure and act.

This is one of the combat principles I was taught.

Though the teachings came from an enemy, strength demands humility. Some claim to fight on emotion alone and still win, but I lack that luxury. Calm strategy is paramount—especially when so many samurai fail for lacking it.

That’s why I refuse to burn hot.

To lose yourself in passion is easy, but victory isn’t.

Rage and resolve can fuel Haki, granting a fleeting edge—but it won’t bridge the gap.

If anger alone brought victory, samurai would’ve triumphed. My parents would still live.

True strength is pure power. Without it, even the finest blade, the fiercest passion, or the rarest Devil Fruit is wasted.

So I grow stronger. Seal away the fury, steel the heart, and train relentlessly.

‘Father, Mother… I will become—a demon.’

That’s right. I swore upon their graves to become an oni and gain strength.

That vow carried me through years among the enemy—unshaken, unmoved.

Nothing will change. Even after this trial, my heart will remain ironclad, emotions locked away until the time comes.

Or so I thought.

"…What are you talking about?"

"Ah, my bad! Got too excited—forgot to introduce myself!"

The towering figure in a horned mask—Yamato—adjusted the spiked club on her back (now dented from KO’ing Page One) and struck a pose.

"—I’m Yamato—Kozuki Oden!!"

"…I see. You’re insane."

Conclusion reached. Talking to her would shatter my tempered resolve like brittle glass. Better to end this now.

"I’m NOT insane! I’m perfectly sane!"

Ignore her. Madwoman always say that. Stay silent, and he’ll leave—

"…Wait, no. Oden was more manly in speech… Gotta work on that."

"WHO SAID ANYTHING ABOUT YOUR SPEECH!?"

—Damn it. My composure cracked. I reacted. This lunatic’s infecting me.

"P-Princess… that one’s unhinged. Be careful…!"

"…I noticed."

Kawamatsu’s warning from the cell was unnecessary. Obviously she’s deranged. Now I’m just depressed.

"Don’t worry! I mean no harm!"

"…Then why is Kaido’s child seeking the daughter of the man he humiliatingly defeated?"

"It wasn’t humiliating!! Oden was a true warrior!! Unlike my cowardly, disgraceful father!!"

"…………"

"Wha… Kaido’s… SON!?"

——Kawamatsu’s shock was understandable.

A child of Kaido—the man every ally of Kozuki hates—stood before us, praising the enemy who defeated him while calling her own father a coward.

What twisted logic drives this Yamato?

"…Why does the son of Kaido—my father’s killer—pretend to be him?"

"I witnessed Oden’s execution 12 years ago with my own eyes!"

"…And?"

"It lit a fire in me!! I was furious—weeping with rage!! My father and Orochi did this!!"

Behind the mask, Yamato’s voice trembled with fervor. Her outfit, I now realized, mimicked Oden’s.

"Someone had to carry his will… So I vowed to become Kozuki Oden—and declared it to my father!"

"…How’d that go?"

"He punched me into next week. Stubborn old fool… I was too weak to fight back then."

"...I see. Even if you're insane, there's logic to your madness."

"I'M NOT INSANE!! I will open this country’s borders!! But right now... I don’t have the strength. The time isn’t right. So I’ve been biding my time, gathering power—until my sister told me about you. The true daughter of Kozuki Oden, Kozuki Hiyori!"

"Your sister... Musashi, was it?"

"Yeah. She’s better at hiding than I am, and her innate Observation Haki makes her ears sharper than anyone’s. ...Well, she’s also kinda nuts and does whatever she wants—"

"Says you."

"But even my crazy little sister helped this time!! When I heard you were being tortured, I came to save you!!"

"...And how, exactly?"

Hiyori cut straight to the point. Explanations could wait—she needed to know his plan.

"You can’t stay here!! They’ll kill you!! You have to leave Onigashima—no, Wano itself!!"

"...They called this a promotion test."

"It’s torture!! No real test would be this cruel—forcing you to either defeat a Tobiroppo or survive seven days just to murder your own ally! You won’t last three!!"

"............"

Hiyori’s brow twitched. "You won’t last." In other words—you’re weak.

So she made her decision.

"—I refuse."

"! Why!?"

"Because of what you just said."

"Huh!?"

Running away? Unthinkable. Unnecessary. She’d make her understand.

"If I can’t last three days... if I can’t win... then overcoming this means I’ll grow stronger."

"!!"

She wasn’t just telling Yamato. This was for Kawamatsu too.

"This place is the closest to my goal. Surviving without strength is meaningless—no different from death. So, Kawamatsu... don’t you dare choose to die in my place."

"...!! M-my lady...! But that’s—! You can’t—!"

"Unnecessary, you say? Then tell me, Kawamatsu—how do you plan to achieve our goal? Did you truly believe it could be done without sacrifice?"

"I would never claim such naivety!! But if you die, the fight loses its hope!! The rest of us will pay the price!! Your blood doesn’t need to—"

"—Kawamatsu."

"!"

She silenced him with his name. His loyalty was admirable—but she had no intention of accepting it.

"Let me make this clear. I... don’t need ‘the future beyond the fight.’"

"!!? What are you—!?"

"I understand your argument. Protecting this land my parents loved, inheriting their will... opening Wano’s borders, avenging them, safeguarding those who’ll carry on..."

Yes, she understood.

But—

"It doesn’t have to be me."

"!!"

"One heir is enough. And this country... the one that spat on my family... I can never love it again."

"M-my lady...!! Ghh...!!"

Her words were final.

Kawamatsu clenched his fists, teeth grinding, tears of frustration spilling. It wasn’t as if she felt nothing.

—But this was resolve.

Throw away everything. Only then could she reach far enough.

Even then, failure was far more likely.

But without that desperation, she could never slay the monster her father couldn’t.

"—Lord Yamato."

"! You don’t need to—"

"No. Right now, I’m a pirate under the Beast Pirates’ ‘care.’ Appearances matter."

"...! Are you sure about this!? If you stay, both you and your retainer could die!!"

"Then so be it. But if you must save someone... take Kawamatsu."

She knelt, centering her focus.

If Page One woke, the fight would resume. She had to be ready.

Yamato and Kawamatsu clearly disapproved—but it didn’t matter.

"If I die here, I was never fit for revenge. Kawamatsu is the more valuable asset. The issue is if I survive without winning... in which case, he dies for nothing. So if you insist on helping, prioritize him."

"...Understood. I’ll do what I can."

"!!? NO!! You can’t—!"

To her surprise, Yamato accepted after a pause. Kawamatsu, however, erupted in protest—ignored as Hiyori bowed to Yamato.

"You have my gratitude."

"Don’t... I can’t even promise I’ll succeed."

With that, Yamato turned to leave—but paused at the threshold.

"...If you live through this, there’s something I want to show you."

“……Are you going to show me your face?”

“Ah—right. Well, just to be safe, remember what I look like.”

With that, Yamato removed his mask—…Huh?

“……You’re a woman?”

“Kozuki Oden was a man, right? So I became one too!!”

“…………”

The tension in the air and this absurd coming-out confession completely shattered my resolve, leaving me speechless. Not that it erased my hatred… but just for a moment, I couldn’t help pitying Kaido a little.

“—Ugh… Damn it…!!”

“! Crap!! Well, I’m outta here!!”

At that moment, Page One finally regained consciousness, and Yamato took off. …She could’ve just left without a word, but her weirdly earnest nature made her look like an idiot.

“You’re awake.”

“Tch… Hey!! Where’d Yamato go!?”

“She left.”

“Che… That damn brat…!!”

He clicked his tongue, rubbing his chest as he got up. As expected, the Ancient Zoan-type’s toughness was anything but normal.

Yamato’s strike had been devastating, but even after being blindsided in a defenseless state, he was back on his feet in mere minutes. That was clearly abnormal. But this was the level of a Flying Six.

And yet, it still wasn’t enough to match an All-Star, let alone the chasm between him and Kaido or King. It only reinforced my belief—I had to get stronger.

“…You. You talk to Yamato about something?”

“…Well, yeah. She tried to get me to escape, but I refused.”

“Refused? …You mean you tried to run but couldn’t, right?”

Page One glared at me. Of course—there was no way he’d trust someone from the Kozuki family sneaking around. He was obviously suspicious.

But I answered his question bluntly.

“—Not a chance. I’m not passing up this opportunity to grow stronger and become a ‘True Combatant.’”

“! …The hell’re you scheming?”

“Nothing… but winning.”

That’s right—I would win.

To defeat the one my father couldn’t. To achieve my vengeance, I’d endure every hardship and overcome them all.

---

I sensed the shift in the air and couldn’t help but speak up.

“—Ah, looks like Yamato’s gone somewhere.”

“That damn idiot…!! —Hey, you bastards!! Go after Yamato too!!”

“Y-yes!! Right away!!”

On the Live Floor, Kaido barked orders at his subordinates, who were already scrambling to treat and carry their fallen comrades.

Musashi was gone—already fled—but sensing his presence, I sent a quick order via Den Den Mushi.

“Jack~~ Head to the back entrance and stall him. You and King can pincer him.”

‘Understood.’

“Don’t get hurt, okay~~♡ Jack’s got important work~ later, y’know?”

‘…R-right. I’ll be careful.’

The ever-serious Jack responded dutifully. Well, between him and King, Musashi wouldn’t last long. He might put up a fight, but it was only a matter of time.

“Haaah… So much work. After this, we grab Yamato, punish ‘em both, head back to Hiyori-chan’s place to watch the fights for a bit… then, uh… what was next again?”

“Aahhh… Yeah, my schedule’s packed. —Hey, Sono!! Tell me what’s next!!”

“Ughhh… As you wish.”

When Kaido called her name, Sono trudged over, flipping open her planner with the world’s most exhausted expression. But don’t let that fool you—Sono was one of the most capable True Combatants. She handled paperwork, schedules, diplomacy, and combat without breaking a sweat. Her only flaw was being terminally lazy. Honestly, she was probably only here because she didn’t feel like chasing Musashi. Not that I minded.

“Let’s see… Sigh—Tonight, you’ve got drinks with Lord Orochi. Tomorrow morning, Lord Joker returns, so after greetings and reports, we’ll squeeze in Jack-sama’s promotion trial. Then in the evening, dinner with two guests—one’s the ‘Warlord’ Donquixote Doflamingo, the other’s Gi—… Ugh, my mouth’s tired. Cancel everything after this for me. I’m taking the day off.”

“You barely even work!!”

The subordinates all groaned in unison. Ahaha, typical Sono.

“What, you that desperate for a break?”

“Sigh… You’re so full of energy, Lord Kaido… Maybe you should rest more? Y’know, like a family picnic or something…”

“…Like they’d even show up.”

“And if they did, we all know how it’d end!! The greatest parent-child brawl in history, reducing the area to ashes!! My lovingly made lunchbox obliterated, and me losing it!!”

“Damn it… Why’re my kids both such morons…!!”

“You said the same thing earlier. Hmmm~ Well, why not ask for advice? Doflamingo’s got life experience—bring it up over drinks!”

“Guess so…”

“Ehhh… So, Lord Kaido, is this like… a dad with a rebellious daughter who says, ‘Don’t wash your clothes with mine!’ phase?”

“…Pretty much.”

(Wait, really!?)

“Ahahahaha!! Well, what can you do? Teenagers, am I right?”

The underlings were stunned, but hey, Kaido was human. Of course he had those struggles… Well, to the outside world, he was this incomprehensible monster, a demon spoken of in whispers. But in reality? He was oddly disciplined—planning meticulously, stressing over family drama, drowning it in booze only to fail. He’d mellowed since his pure-brawn days.

“There’s gotta be a way… Hey, King. Stop smirking and help me out here.”

"Hmm~~~ Uhhh… How about making more time for family!! …Or something?"

"I already try. I always call ‘em for meals, but they ignore me."

"Well, they do hate you. Plus, you always drink. Most kids hate it when their parents drink during dinner, no? Dunno, though."

"When I invited ‘em to the baths, they fled Onigashima."

"They’re both girls—well, not kids, but y’know, puberty or whatever?"

"I discipline ‘em properly when they act up."

"Your ‘discipline’ is a Thunder Bagua… I mean, it does make ‘em stronger, so whatever…"

Honestly, if that’s your go-to parenting move, no wonder they avoid you. …Well, not that that’s the real reason. "Hate" isn’t quite the right word either.

"—Ah, speaking of which, Jack just…"

"Oi, caught ‘im?"

I nodded. From the presence I sensed with Observation Haki—

"Got slashed, didn’t he?"

"THE HELL!?"

"Aah…" Looks like he got hurt after all. But hey, he’s tough. He’ll live. King’s catching up too.

---

—Onigashima’s Back Entrance

Onigashima had multiple entry points—front, back, even the sides.

Jack’s role was to block all of them and stand guard.

"—Lord Jack!! The back entrance is sealed!!"

"…You lot, stay on standby."

"Yes, sir!!"

Jack gave the order and waited.

King’s intel said the target would arrive soon.

There was no such thing as too cautious.

Because the enemy was that strong.

"—Took you long enough, Musashi."

"Muu—! So it is Jack!!"

The moment the girl’s feet touched the ground, Jack locked onto her.

Twin blades already drawn, stance ready.

"But fret not!! Such trifles shan’t bar my path…!! Behold… the world’s strongest slash!!"

—Shit.

A split-second delay. The girl exploited it, darting into his guard.

"— Peach Blossom Ten Fists!!! "

"!!"

"L-LORD JAAAACK!!?"

A shallow gash split Jack’s chest. He coughed blood—but glared and raised his blade.

"! —Fuhaha!! Tough as always, I see!!"

"Gh… Musashi… By Lord Kaido’s orders… I’m taking you in…!!"

"Then finish me before the old men arrive!! If you can!!"

The girl grinned, relishing the clash as her Haki collided with Jack’s head-on.

"Such insane sword skills…!!"

"Lord Jack got cut…!!"

"!! —Fufun. You lot have taste. To recognize my blade!"

"Uh… N-no, we just—"

"Very well!! Since you’re so eager… I shall grace you with my name!!"

"W-we know who you are—"

The Beast Pirates stared, baffled, as the girl puffed up with pride.

Everyone knew her. She was Kaido’s daughter, after all.

But she wanted the theatrics. Eyes gleaming crimson, she struck a pose.

"I am… the Red-Haired Flower Sword, Kozuki • Shimotsuki • Juraqyl • Fuus • King—MUSASHI!!!"

"TOO DAMN LONG!!"

"AND YOU JUST MASHED WORDS TOGETHER!!?"

The pirates gaped. Musashi remained unshaken.

‘Kaido’s Daughter (Self-Proclaimed "Kozuki Oden’s (Sword-Saint) Daughter") — MUSASHI’

"Hmph… Fools with feeble hearts cannot comprehend… How stifling!!!"

"Now she’s just spouting nonsense!!?"

"Get a grip, Lord Musashi!!"

The pirates questioned her sanity. But Musashi’s focus was solely on Jack—now with his blade drawn.

"Hooh… Now that I think of it, Jack does use a sword… And he’s strong… Perfect. I’ll make you my Papa too!!"

" MAKE ME YOUR WHAT!? "

"WHO EVEN SAYS THAT!?"

Their protests were endless. Her words were that deranged.

And in that moment—Musashi closed the gap again.

Her blade flashed toward Jack as she declared:

"And so… You understand, yes? You shall impart your swordsmanship… to me, your new daughter—!!!"

"…!!"

"SHE’S INSANE!!!"

The clash of steel erupted at Onigashima’s back gate, ringing endlessly.