The Protagonist's Sister Is Actually The Strongest

As I saw Zero One hacking the Mechanical Tree, almost a dozen Heaven Fragment Machines rushed towards her. Their shapes and forms were just as I remembered them, with sharp arms and legs and overflowing with Heavenly Ki.

They couldn’t cultivate this energy, but through their special forms, they could control it—a new type of machine created in this world to adapt to its supernatural energies and fight and defeat even Immortals!

“Please, show me more of what you can do, as the last member of humanity,” Zero Two was enjoying our fight, her two sharp blades clashing against my four swords at once.

Heracles Axe-Sword, Gram, Oblivion, and Qin Xiuying combined their Sword Auras together, as I unleashed a barrage of slashing attacks in conjunction with my Skills and Martial Arts.

“{Myriad Blade Arts}: {Divine Dance Between Heaven and Hell}”

SLASH! SLASH! SLASH! SLASH! SLASH!

A storm of slashes was unleashed against Zero Two as I danced, evaded, spun, circled, and jumped around her entire body; her blades were unable to follow me, and hundreds of attacks engulfed her.

Her incredibly tough body rapidly began to fall apart into pieces, yet swarms of Nanomachines appeared around her, trying to repair her and combine with her, quite literally regenerating her wounds!

“Ungh…! Your power is incredible, but as long as I am within the Mechanical Tree, my power is endless! And I will not stop until my mission is finished. Human or not, I shall eliminate you.”

Zero Two roared, her crimson eyes glowing brightly. Her entire body overcharged with electromagnetic energy as she attacked me, her two swords fusing into her body and forming an even heavier armor, making her resemble a high-tech black-colored mech with red neon lines over her body.

CLASH! CLASH! CLASH! CLASH!

With two massive, indestructible mechanical fists, she attacked continuously, pushing me back as I clashed against her. Within her, I could also feel fragments of Black Heaven—at least four or five of them! Is this the source of her tremendous power?

While Zero One had to train for it, she got it from birth, huh!

“Enough.”

I stepped forward, and then, overcharging all my Aura with Lightning, I unleashed a hundred thunderbolts with each swing of my sword against her.

BOOM! BOOM! BOOM! BOOM!

“Aaaghh!”

Zero Two’s body began falling apart into pieces again, yet more and more swarms of nanobots appeared, trying to help her; at the same time, what remained of her armor formed into a huge cannon in her chest.

“I will eliminate any threat as I am told!”

TRUUUM!

The crimson beam of pure red plasma reached me in an instant. I put all my swords in front and my Aura, protecting my main body from the explosion.

BOOOM!!

The plasma could melt almost anything. I quickly felt my skin beginning to rapidly boil. I decided to go harder this time, putting a veil of cosmic energy on my body, and then…

“{Bleeding World}”

“Huh?!”

RUMBLE!

The ground and the skies trembled as Zero Two was encompassed in a world of blood. Everything was blood; the sky was blood; the ground was blood; everywhere there was blood.

And screams, the endless screams of a Void Ruler whose very existence is the embodiment of the Universe’s suffering.

“GRYYYAAAHHHH!”

Her scream echoed, and then it echoed; countless screams followed. Zero Two was unable to understand what was happening, but endless blood consumed her.

“W-What is this?! I can’t process…! My mind… My- UGH! AAAGGGHH!”

BOOOMMM!!!

And then the Bleeding World collapsed, exploding on its own pseudo-domain; all of the assisting nanobots were vaporized, and Zero Two lost both of her arms, while the rest of her body was riddled with cracks.

She fell from the air, hitting the cold floor beneath, vomiting blue-colored liquid, perhaps some sort of coolant within her own circuits.

“A-Ahh… What… what was that?”

I could have gone harder against her and used stronger techniques, but I didn’t want to kill her. If she’s like Zero One, then she can learn; she has feelings and can change.

“Nanobots… Help… Ugh!”

However, her eyes widened when she noticed her surroundings were encompassed by Abyssal Flames, which I conjured using my gauntlet.

“Give up; you’re done for,” I said. “Stop fighting and resisting… It’s all pointless. Selfishly trying to claim this world as yours will never lead to a good ending. It’ll only bring you more despair, more agony… Do you truly want that?”

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“It’s… my duty…” she muttered, suddenly smiling. “But by now, Zero One must be already dead, right? Hah… you failed anyway.”

“Oh? You think so?” I smiled back at her.

“Huh?!”

Suddenly, she glanced at Zero One, who was constantly expanding her Will across the Mechanical Tree, rapidly spreading her blue circuits against the red circuits.

“T-That’s…! She’s fine?! Where are the- Ah?!”

The Heaven Fragment Machines were all splattered over the floor, their pieces broken and shattered, as a group of Death Apostles had finished them off for good, accompanied by the two Primordial Beasts, who managed to sneak inside right after we jumped into the Mechanical Tree’s interior.

“N-No…! When did you summon them?!”

Zero Two panicked, screaming in anger as she kept coughing, electricity coming from her mouth and her large “wounds”.

And well, I’m not going to just tell her how I did it...

But it was fairly simple; I simply moved where the Portal to the Purgatory opened, I placed the portal down below, and when we jumped from place to place with Zero Two, I summoned the Death Apostles.

She was unable to see it because I reduced the portal to a very small size thanks to the power of Jeremias’ spatial manipulation!

Hah, I bet she never thought I could do such insane things.

She’s strong, but at the end, she’s only a desperate measure of the AI of this Mechanical Tree.

FLASH! FLASH! FLASH!

As she kept yapping, Zero One’s circuits continued expanding, more and more and more. Over time, they covered almost the entire Mechanical Tree.

“Hahh… Hahh… Please, just… don’t fight anymore and be a good… machine!”

With all her power, especially all the energy she had cultivated so far, a thunderous roar echoed, and all her circuits became lightning itself, destroying the red circuits opposing her.

BOOM! BOOM! BOOM! BOOM!

“ERROR. ERROR. ERROR…”

“FOREIGN… PROGRAM… OVERTAKING… DATA… CHANNELS…”

“ARTIFICIAL INTELLIGENCE CORE… IN DANGER…!

“WARNING! WARNING! WARNIIIIIIIIIIIII-”

Then, the voice of the Mechanical Tree went silent.

And then, everything started glowing bright blue.

Yes, everything!

FLAAASH!

Silence overtakes the entire Mechanical Tree.

All the machines trying to get inside suddenly stopped moving.

The Death Apostles glanced around in silence.

“Was that it?” Neberius wondered.

“Hahh… Hahhh…”

Zero One was gasping; she didn’t need oxygen to breathe, but it probably meant her entire body was overheating; therefore, she was absorbing oxygen to cool down.

“Zero One!”

I ran to her side, quickly catching her before she fell to the ground.

“D-Did it work?”

“Phew…”

She smiled cutely, her eyes shining bright blue.

“Yes… I did it! Anna… No more of my kind has to die…”

She really did it…

I was already getting ready to just destroy the whole thing if she failed, but…

She didn’t disappoint me.

Zero One’s truly amazing!

“Well done!”

I hugged her tightly as she hugged me back and happily caressed my head.

“Thank you, Anna; without you, it wouldn’t have been possible! T-This is only the first of three, but…” she muttered. “We’ve already taken such a big step forward! This is just… incredible!”

“I know, right?!” I laughed. “We can do it; we can save this world, and we can also save the machines! Just like you wanted, Zero One. Let’s create a world where both can live together.”

“Thank you, Anna…”

She started crying, part of her way to show her emotions, hugging me and sobbing over my shoulders.

“Thank you so much…”

“It’s okay…”

I patted her head and carried her like a princess, walking to the side of the Death Apostles and the Primordial Beasts.

“Well done everyone! Thanks for the help.”

“Ah, it was good to finally get back at these bastards,” Agares smiled, crushing the pieces of metal left behind by the heavenly machines.

“Right, you guys got fucked by them back then…” I nodded. “Woah, this means you’ve grown much stronger than before, huh?”

“But of course, CRAAAH! Do you think we just stay weak or something?!” Neberius angrily said. “We’ve been cultivating Ki and mixing it with Demonic Energy on our own accords and techniques. Slowly regaining more of our former strength as we cultivate Souls and Demonic Bodies alike!”

“It’s a slow process, but we’ve progressed enough to not have problems against these at least,” Aim said. “What’s next though?”

“We’ll rest for now, so well done,” I said. “But we might have to go against the other Mechanical Tree pretty soon, so stay sharp. Also, I’ll give you some rewards, here.”

I opened the Urn of Souls and fed them twenty fresh souls each.

“Oooh, fresh souls?! And so many, for us?!” Aim was drooling.

“Hmm! I was so hungry! Hahaha! Maybe it’s not too bad to serve you for now, you damn brat!” Astaroth laughed.

“CRAAH! Souls! Souls! Nam! Nam! Nam!” Neberius was catching them with his beak as if he were a baby chick being fed worms by their parent.

“Hm, thank you for the meal,” Agares seemed pleased.

“A generous reward; I suppose you expect more of our help, hah,” Bael said. “Well, as long as we’re well paid, we don’t mind helping you for now…”

“Jeremias, you won’t eat your souls?” I wondered.

“Um, I prefer absorbing Spirit energy,” he said. “I am not a demon after all, but a Demonic Spirit, master…”

“Right…” I nodded. “How about this then?”

I quickly clenched my fists tightly, giving him a large crystallization of spiritual energy I had within my body.

“This is a Spirit Ki Pearl, I made it! It should be a good snack?”

“Oooh! Yes, thanks!”

He ate it immediately.

Aren’t they cute in their own twisted and demonic way?

[“I can’t believe you’re treating these embodiments of destruction as pets… You’re insane.”]

Gram was annoying as usual.

Not in the mood to engage with this toxic sword.

Ignored!

Or maybe not.

”Well, they’re under my wing, so I need to take care of them…” I sighed. ”Also, they’re just demons that lost everything and became twisted because of that. But they never truly meant any of the atrocities they did, right guys?”

“We meant them.”

“Yes, every one of them!”

“We love killing and destroying.”

“It makes life worth living.”

“Ahem! Well, maybe they meant it, but… As long as I’m taking care of them, they will not do any of such things anymore! Ok?!” I said to my talking sword.

[“Sure, sure, whatever you say, Anna…”]

He’s treating me like I’m insane!

“Um, Anna, can you let go of me? I think I’m feeling fine… now…”

Zero One looked embarrassed, blushing a bit as I carried her.

“Are you sure? You looked very tired, so I don’t mind bringing you back to master’s Inner Realm to-”

“N-No, I can go on my own, ahaha… it’s embarrassing!”

“Okay, okay, I’m sorry.”

I let her go as she quickly sighed in relief.

“Thank you for helping, Death Apostles! I don’t have much to give you as a thanks, but…”

“Don’t worry, we got plenty,” said Agares.

“We absorbed some Heaven Fragments, heh,” Bael smiled.

“We’ll grow even stronger, no!” Astaroth laughed.

“O-Oh, well, if you liked that, then I’m happy!” Zero One smiled innocently, without knowing she was talking with monstrous demons.

“Let’s go then. I believe you want to have a talk with a certain someone, an evil sister of sorts…” I said, glancing at her eyes.

“R-Right! Zero Two! You didn’t kill her?!” wondered Zero One.

“Nope, I knew you would want her alive,” I sighed. “So I went easy on her. She’s over there; let’s go.”

We ran towards Zero Two, amidst hundreds of machines glowing blue, who glanced at us with innocence.

“How did you overwrite their programs, Zero One? Is it like… brainwashing?”

“N-No, machines work differently than living beings. The reason they were so aggressive is because of protocols they must obey. Forcefully imprinted into them. I simply “freed” them from it, giving them the ability to think for themselves.”

“Wait, so they joined us all because…”

“Yes, because I freed them from their primary orders.”

So that’s how it works…

Then, could it be the same for her little sister?

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