The Protagonist's Sister Is Actually The Strongest

Once finally reunited with the rest of her family as they confronted Lucifer, Anna unleashed her new powers after “taming” Legion.

She had realized only recently that these Demons and their Demonic Energy-based powers were remarkably effective against Lucifer.

Though far weaker than he was, they held their own by fighting as one, defying the overwhelming odds.

It was only a theory, but Anna had begun to understand that beings with similar Story Origins could inflict greater damage on each other.

And perhaps that was also why some monsters proved so brutally tough for human hunters. A clash between the laws governing their worlds created distortions that strengthened them against beings of different origins.

Hence, Anna concluded that fighting fire with fire was the best option against Lucifer. She summoned her Demons and activated her new ability to combine them, unleashing their latent potential.

She was surprised by how deep their bonds ran; they were far more than the one-dimensional beings portrayed in the novel.

In fact, no one was. The novel offered only a surface-level view of events, seen mostly through Jack’s perspective. Naturally, foes he slew in a single battle and never encountered again had no chance to reveal their real backstories.

But because Anna had given them all a second chance to atone for their past and work together with her toward creating their own world—where Demons could finally live in peace, free from Lucifer’s tyranny—they were beginning to show their true colors. Their personalities, their bonds, everything that made them who they were emerged. Just like Inferna and the other Demons she had helped, Astaroth and the rest proved far more complex. At the end of the day, they were people too.

“You’ve shown me your beautiful bonds! So combine and unleash your latent potential! I bless you with the power of Love!”

Though the words sounded cringy to her, Anna spoke them without hesitation. She had learned that her Love and Princess Traits worked best when expressed verbally. As cringy as they sometimes felt, her words ignited the hearts of the Demons and her family with renewed strength, blooming into pink flames of love.

FLAAASH!

“RAAAAHHH!”

Astaroth and Aim screamed as their bodies fused, merging into a gigantic demon unlike anything they had seen before. It resembled a golden dragon encased in armor of crackling thunderbolts, covered in leopard-like markings across its golden scales, with six powerful arms and gigantic fur-covered wings.

As the other Demons witnessed this new, monstrous, and overwhelming form, they began to combine one by one—even against their own will.

Neberius and Agares merged, manifesting a giant black knight clad in crow-like armor, bearing four black wings and wielding a powerful shadow sword.

Jeremias and Bael combined as well, creating a tall, muscular, red-skinned demon with an impish face, dressed in black and red armor and carrying a staff topped with a glowing cubic artifact.

And finally, Anna combined Legion and Nemesis, forming a giant bird-faced mechanical goliath with hundreds of mechanical arms surging from its back.

“W-What in the world is this?!” Neberius and Agares spoke in unison. “CRAAAH!” Their fusion seemed dominated mostly by Neberius’ mind, surprisingly.

“I feel… No, WE feel stronger now!” Jeremias and Bael said. “Yes, this power…! Jeremias, I’ll show you how to truly use it!” Bael had overtaken Jeremias with ease, seizing control of the fusion.

“GRUOOOHHHH!” Legion and Nemesis, being the same type of demon, got along seamlessly.

Each fusion radiated tremendous power like never before. Their combined strength far exceeded the simple sum of their individual levels.

This meant fusion made them vastly stronger than if the two had merely fought together against a foe.

Though they also sensed the technique’s instability—their souls and bodies constantly shaking and trembling—they would need considerable practice to master this new ability.

As Anna finished her preparations, Lucifer was already charging toward them.

“I’LL KILL YOU ALL!!!”

He was utterly furious at the sight before him. To see these weaklings he had long scorned combine and draw forth even greater power was sacrilegious. It was an insult to use something as foolish and undemonic as “love” and “hope” to amplify their strength.

Lucifer believed in the true demonic way: demons must devour one another to grow stronger, inheriting the strength and soul powers of the devoured.

Only the strong deserved to survive and prosper through endless growth and consumption.

The weak? They were nothing but food for the strong.

But Anna’s ideals and the way her powers functioned defied this primordial law that governed not only the 999 Hells, but perhaps the entire Multiverse.

Only by being utterly selfish and caring solely for oneself can one prevail and survive. Bonds, friendship, cooperation, all of it was meaningless in the face of the universe’s cruelty.

Lucifer had watched countless worlds fall, one after another, reinforcing his belief that this was the only true path.

But now… that was about to change. His ideals were being challenged by the human girl who had killed his “pet.”

“GO!”

As Anna roared, she charged forward, leading her entire group. The fused Demons surged past her on both sides, unleashing their combined demonic auras.

The Heavenly Empress and her son followed close behind, while Fang Shuan, within Anna’s golden armor, rapidly expanded further through her body.

“For this, I have to go even further beyond… My Heavenly Princess of Love Transformation must merge with my Golden Morphin Armor…!”

{Mighty Morphin Mechanical Armor: Four Cosmic Golden Beasts of Hope}!

Anna began combining her two strongest forms. Cosmic power, heavenly ki of hope and love, and cursed ki from her demonic marks converged with Fang Shuan’s mechanical armor. They mixed further with the Cosmic Souls of Sepa and Bastet, along with her White Tiger and Shadow Fox Transformations.

“HAAAAAHHH!”

As she met the titanic draconic claws of Lucifer’s vessel, Anna’s clothes and armor merged in a brilliant flash, covering her in beautiful pink and golden armor adorned with hearts, feathered wings, demonic wings, cats, centipedes, tigers, foxes, and more.

[You have activated the Fusion Skill: [Mighty Morphin Mechanical Armor: Four Cosmic Golden Beasts of Hope (SSS): Lv1]!]

[All of your Equipment—Armor, Accessories, Helmet, Gloves, Weapons, Swords, Shields, and everything catalogued as Equipment—has temporarily merged into the {Mighty Morphin Mechanical Armor of the Four Cosmic Golden Beasts of Hope}!]

[Their Stats have converged into this single piece of armor covering your entire body, and their combined Stats have been further boosted by 400%.]

[Additionally, your Armor will continuously grow in Toughness, Defenses, Attack and Agility Boost, and Energy-Channeling Capabilities the more damage it takes, with each direct blow increasing this boost by 1%.]

[You have additionally gained the ability to summon powerful pieces of equipment through the {Mighty Morphin Weapon Manifestation} Ability, which will contain the power of your Weapons combined, with unique effects and powers based on each of the Four Golden Beasts.]

[The {Four Blessings of the Golden Beasts of Hope} have been activated in quick succession!]

[The {Blessing of the Golden White Tiger} increases your Physical Prowess by 500%.]

[The {Blessing of the Golden Cosmic Millipede} increases your Defense Piercing Power by 250%.]

[The {Blessing of the Golden Sunshine Cat} increases your Agility, Dexterity, and Movement Speed by 300%.]

[The {Blessing of the Golden Nine-Tailed Black Fox} increases your Magical Prowess by 500%.]

[All Blessings are in Effect for as long as the Armor is activated.]

[The Armor is continuously draining Ki and Cosmic Energy…]

[You have further improved the Armor with the power of your {Heavenly Princess of Boundless Love} Transformation.]

[All of the Armor’s Bonuses have been further increased by 100%, and you have gained more fuel through the assimilation of Heavenly Ki of Love and Hope.]

As Anna scanned the notifications, she quickly materialized several katanas made of golden light, keeping only Gram from fusing with the rest of her armor.

CLASH! CLASH! CLASH! CLASH!

Her swords collided against Lucifer’s claws as the monstrous dragon—still growing wildly while summoning and devouring demonic beasts to restore his energy—opened his many jaws, preparing to unleash seven dragon breaths at near point-blank range.

“DIIEEEEE!”

All seven draconic heads roared, releasing spiraling beams of black and red flames that twisted and warped space as they hurtled toward her.

However…

“Not on my watch, filthy demon!”

Her aura erupted. The figure of Fang Shuan emerged from within, wielding a giant spear of pink and golden flames. Through his fusion with her armor and powers, he could temporarily become her Ego as well.

His form was more than that. He quickly divided himself into dozens of copies. Once a monster trapped in a dungeon, Fang Shuan had regained his sanity and true memories thanks to Anna. Through their journey in Bestia, he had learned many new things and continued to grow without end.

His soul blazed with immense power as he synchronized with Anna’s attacks, unleashing his strongest technique multiple times at once and overwhelming Lucifer in a single second.

“{Golden Dragon Spear Techniques}: {Golden Dragon’s Ascension}!”

”ROOOAAARRR!”

The technique struck Lucifer dozens of times in that brief moment. His draconic breaths shattered against golden dragon-shaped explosions of ki that erupted from the Soul Spears Fang Shuan conjured one after another.

BOOOM! BOOOM! BOOOM! BOOOM! BOOOM!

”UUUGGHH...?!”

As the King of All Evil took massive damage repeatedly, he desperately devoured his own summons to recover.

Clinging to life, he was being pushed to the absolute limits of what his created vessel could endure.

And his soul?

It was riddled with more and more cracks…

-----