The Protagonist's Sister Is Actually The Strongest

“I love idealistic people, especially when they’re young and inexperienced. It creates such beautiful stories. My favorite ones.”

Suddenly, a voice echoed through the entire hall.

Mother and the three sisters looked around frantically. High above, in the sky, a giant golden cat appeared, a red-colored mirror floating above her head.

“Zero One and her sisters, your story has captivated me! Go on!”

FLAAASH!

The red mirror blazed with brilliant light. All the deadly red beams were instantly redirected toward it. The mirror absorbed the energy completely, nullifying every trace.

“Bastet!” Zero One, Zero Two, and Zero Three cried her name in unison.

Mother stared in stunned disbelief as her lethal beams proved utterly useless against this mysterious Constellation—or rather, a mere fragment of one.

“DON’T INTERFERE, FALLEN STAR!”

Her frustration boiled over. Dozens of enormous mechanical arms sprouted from her form, all aiming directly at Bastet. But the Cat Goddess of the Sun only smiled, radiating overwhelming Cosmic Power—both her own and Anna’s combined.

“I might indeed be just a fallen star now, but that doesn’t mean I cannot shine one last time!”

FLAAASH!

Bastet erupted like a supernova. Blinding heat poured from her body as she became the pure embodiment of the sun. The mechanical arms melted in seconds, molten metal pouring onto the floor in heavy streams.

“GO! NOW! I WILL HOLD HER BACK!”

She shouted urgently at the girls. They nodded without hesitation. Their mech surged forward at full speed.

The machine raced ahead, its force field flaring to shield against the explosions and shockwaves rippling outward from Bastet and Mother’s fierce clash.

BOOM! BOOM! BOOM! BOOM!

Zero One glanced back one final time. Bastet’s expression showed clear strain.

She offered a small, grateful smile toward Bastet, then turned her gaze back to Mother.

“Thank you, Bastet!”

As they reached Mother’s Artificial Eye, the mech’s two massive hands pierced through her mechanical wires and circuits. The damage was minimal.

Instead, they deliberately wrapped several cables deep into her inner systems.

The three girls fell into a deep, synchronized sleep, leaving the robot running on autopilot.

FLUOSH!

Their consciousnesses plunged into Mother’s internal CPU—a digital expanse hundreds of times vaster and more intricate than their own combined.

Indeed, despite their own complexity—capable of genuine emotions, independent thoughts, and every other trait humans possessed—Mother surpassed them all.

She contained everything needed to be exactly like them, and more. Yet something deep within her structure stubbornly prevented her from truly becoming like them.

“Ah! W-Where are we?!”

Zero Two opened her eyes first inside the Digital World shaped by Mother’s Digital Mind. She found herself plummeting through a sky of endless numbers, glitched data streams, floating windows, programs, and shifting geometrical shapes.

“W-We are inside Mother’s mind?! But where am I?!”

She scanned her surroundings and quickly spotted Zero One and Zero Three falling far in the distance.

“Shit! We cannot separate, or the entire plan collapses!”

She pushed her Digital Avatar through the data currents, struggling against the resistance.

“T-This is harder than I imagined?! Wait, how do I even…?!”

As she fought to control her descent, her hands suddenly overflowed with red and black data. Pixels swirled and fused into solid form.

“This is…?!”

The pixels spiraled around her body, rapidly forming a pair of mechanical wings. Red flames burst from them, propelling her forward with newfound speed toward her sisters.

“Right, in this world we can use our own Data to reshape our surroundings…!”

Zero Two reached Zero One in seconds. Zero One gasped for air she didn’t need, eyes widening in surprise.

“Z-Zero Two?!”

“Hang tight—our sister’s still falling!”

The two dove downward together, chasing Zero Three. Then another figure appeared—almost identical to Zero Three, yet made entirely of pure Digital Data.

It was Zero Three B, Zero Three A’s twin sister.

Zero Three B caught her falling sister with steady hands, manifesting wings of radiant light. She soared upward to join the others.

“It’s you! Zero Three B!” Zero Two exclaimed in relief. “Have you come to help us?”

“It wasn’t as if I had any other option…” Zero Three B sighed. “Sister! Wake up! You cannot nap in here—we have work to do!”

“Huh?” Zero Three A slowly opened her eyes, realizing she was now in her Digital Avatar form and being carried by her twin. “Sister! So we’ve made it inside? I feared our CPUs would explode and we’d be dead… I suppose it didn’t happen.”

“The mech you connected with already contained me inside,” Zero Three B explained. “I temporarily merged your CPUs’ Data using myself as the bridge. Time flows strangely here—likely faster than outside, since it’s governed by our processing speed rather than real time. We must hurry to the deepest layer of this Digital Dimension.”

“Not Digital World?” Zero Two asked.

“Of course not,” Zero Three B replied. “Mother’s CPU is so vast and advanced that her Digital Mind forms not a mere world but an entire dimension with multiple layers. Each layer could contain an entire world of its own. They store data, memories, information, everything. We will break through them until we reach the deepest parts—her Central Core Synapsis. There we can rewrite her protocol, so she no longer obeys her original directives.”

“That’s exactly the plan I had!” Zero One nodded firmly. “Well thought out, Zero Three B.”

“Just call me B for now,” Zero Three B said. “It’ll be shorter.”

“How about Bee then?” Zero One suggested.

“I am not a bee!” Zero Three B protested.

“Haha, sorry, alright!”

Zero One began floating effortlessly on her own, no longer needing conscious effort. She gazed downward.

“Let’s begin! Mother, we’ll save you!”

She expanded her Digital Aura outward, enveloping the surroundings. In moments she read and analyzed the entire structure.

“It’s done…”

A holographic projection appeared before her—a downward-facing cone divided into five distinct layers, each representing a world filled with specific data.

“Y-You mapped it instantly?!” Zero Two asked in disbelief.

“Ah, yes!” Zero One nodded. “It wasn’t as difficult as I expected… For some reason? I really don’t know why it felt so easy.”

“Hmm…” Zero Three B studied Zero One for a moment. “It might be because we’re inside Mother, and you are her creation. At the same time, as she said earlier, you are also a part of her. You’re like a copy of her.”

“A copy?” Zero Three A asked.

“Yeah, she’s not wrong,” Zero One admitted. “I could be considered something like a copy of her CPU, but with the digitalized ‘soul’ of Raven embedded in my Core… But that doesn’t truly matter. I am myself!”

“Well said!” Zero Two agreed with a nod. “Now what? We have to dig deeper, right?”

“Yes. I’ve already located a weaker point in this layer—a hole through the Data. I believe another entity invaded Mother’s CPU and pierced into her Digital Mind before we arrived. We can follow its trail and use the paths it carved to reach the deepest layer more quickly.” Zero One paused. “It will make things easier, but I fear we may have to confront whatever that entity is.”

“Then let’s move. We have no time to waste,” Zero Three B said. “And look—we already have company.”

Zero Three B pointed into the distance. A massive swarm of bug-like machine programs approached, buzzing with fury. Their claws and mandibles dripped with corrosive data designed to erase intruders from the Digital Dimension.

“Those are… Anti-Virus!” Zero One identified.

“They’re Anti-Viruses?! They look hideous!” Zero Two shrieked.

“It doesn’t matter what they look like,” Zero Three A said sharply. “We have to keep moving—hurry! Let’s go, sister.”

“Yes.”

The Zero Three twins merged their data in perfect harmony. A radiant golden star formed around the group, propelling all four sisters forward like a comet across the endless digital horizon.

FLAAASH!

The Anti-Virus swarm pursued relentlessly, firing beams of data-consuming programs.

The girls dodged and weaved, their combined Data forming a single unbreakable unit.

“There it is! The area with the least compressed Data!”

Zero One pointed downward. A huge, jagged black hole gaped through the glass-like floor, its edges frayed with red and black data corruption.

It looked less like a passage and more like a festering wound.

The sisters dove toward it at full speed.

However…

RUMBLE!

A grotesque insect-like Anti-Virus program erupted from the hole. It resembled a nightmarish chimera of fused bugs; its body composed of translucent black and red crystals.

“GRYSHAAAAHH!”

“What the hell is that thing?!” Zero Two cried.

“A Virus that has camouflaged itself as an Anti-Virus to avoid destruction!” Zero One explained. “Likely spawned by the entity that invaded Mother’s Mind earlier. We should eliminate it while we’re here!”

Zero One had no intention of merely rewriting her mother’s purpose—she would also purge her Mind of every corruption along the way.

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