The Protagonist’s Sister Is Actually The Strongest [An Action-Packed LitRPG Transmigration and Progression Fantasy]

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The agonizing scream of the Archdemon of Gluttony, Uroboros, echoed across the entire World, and even within the Realm Beyond, where his entirety had been located seconds before he foolishly attempted to devour Fenrir and Anna to gain even more power. Even though he would have received great penalties, he believed the gains would outweigh the losses.

However, in the end, this endless hunger for power and his recklessness as someone who has never faced true defeat after always plotting and scheming against others and backstabbing him turned into his deadliest curse.

With Fenrir, Jack, Henrietta, and Anna’s strength, Uroboros was cut through from all sides, and Anna finally struck him down, piercing the core of his Soul, his Soul Heart, the very center where his Dao Branches and Dao Roots originate from.

Because of the penalties of descending into a low-level dimension, most of his Traits and powers were sealed, giving them the golden opportunity to slay him!

Naturally, the death of a Constellation was no laughing matter, even less that of an Archdemon. Even though they were usually considered foes of most Constellations, they were still powerful enough to hold great authority within the Unified Worlds of the Realm Beyond.

“How is this possible?! Uroboros truly died?!”

“No… How come mortals that had yet to even become Pseudo Constellations do this?!”

“They’re not even Death Apostles or Virtue Saints either!”

“But they received the help of Fenrir; as sealed as his powers are, he is still someone who can threaten our existence! That damned God-Devouring Dog!”

“They are still within the First Awakening; where did they get this much power?! Not even with Fenrir’s aid would this be possible!”

“Uroboros, you utter fool! You’ve brought disgrace to all of us now!”

“Those humans… They’re dangerous!”

This swiftly caused an uproar. As both evil, righteous, and neutral Constellations panicked, most of them felt complete and utter disbelief that a literal God was slain by a mortal that had yet to ascend into a Constellation themselves.

The High Administrators of the Realm Beyond only watched things happen in silence before closing the cracks that led to this higher-level Dimension before any more of its dangerous energies could leak into the Low-Level Dimension containing Earth.

“This is the first event to have happened in all of history for humans to slay Constellations…”

“This world, Earth, was it?”

“We’ve underestimated its growth potential.”

“If they believe they’re so strong, then I suppose they don’t mind us hastening the Awakening process, right?”

Many High Administrators smiled as they took a drastic decision that would later affect the entire fate of planet Earth and its inhabitants. 

Meanwhile, within Jack’s Soul Scape, Uroboros slowly disappeared from there, leaving behind hundreds of Constellation Soul Fragments, which Fenrir swiftly devoured.

The seals sealing his powers slowly came undone through the surplus of new power, until none of them were left at all.

FLASH!!

An enormous amount of power erupted from his own Soul, already fused with Jack!

“T-This is… We truly defeated Uroboros, and this bastard’s soul truly tasted delicious.

As Fenrir laughed, his powers slowly started to recede; if he let them go without restrictions, they would quickly destroy Jack, as he was not enough of a vessel to harbor a whole constellation merged inside.

His own chains wrapped around his soul; this time, he chose to seal himself to protect Jack. He could even choose to ascend by himself now, but that would only kill Jack in the process.

He had truly changed and simply couldn’t go while leaving behind his friend and the family they had.

“I will restrict these powers now for you, my friend. You have to quickly grow stronger, so we can unleash it all against those bastards.”

As Fenrir’s words resonated through Jack’s soul, the young man finally woke up, opening his eyes to find himself sitting over a pile of rubble. Henrietta was hugging him at his side, her aura constantly healing his body.

“Henrietta?” Jack muttered.

“Jack!” The blonde girl quickly hugged him even tighter, kissing his lips. “I was so worried! I-I can’t believe it... Did we really kill a Constellation?! I didn’t know that was even a possibility!”

“For mere humans like you, it wasn’t a possibility.” Fenrir manifested himself beside Jack in the form of a giant black wolf. “However, thanks to my help and Anna’s help, it was possible.”

“Wait, Anna was also...?!” Henrietta asked.

“Yes, she was fighting with us.” Jack nodded, standing up. “On the other side...”

Jack said these words as he saw countless System Boxes pop up in front of him. The amount of EXP he gained by slaying a Constellation was utterly insane.

His Level, which was at the cap of 250, quickly went all the way to 231/250 from 84! And even then, this was a restricted amount; just as Uroboros powers were restrained, so were the rewards he could give when slain.

Each Level Up enhanced his synchronization with Fenrir without harming his soul, making him more accustomed to the now fully unsealed powers of the Fallen Constellation.

With strength surging from his body, his sharp senses quickly glanced at the battle in front of him. A giant Rock Dragon Man was battling three Hunters at once.

Dimitri, Hilda, and Scarlet were doing their very best to keep him in check, but they were already on the losing side.

Gustavo’s regenerative abilities were on a completely different level, and he kept regenerating while spamming all matter of Earth Magic.

While he seemed to have unlimited stamina, the trio didn’t.

“That big snake’s presence is gone.” Gustavo thought. “But what is this presence I’m feeling? Something... Almost as frightening?”

As Gustavo was about to give Dimitri a finishing blow after knocking him unconscious, a sudden flash of darkness appeared behind him.

A powerful and painful pressure quickly covered his entire body, immediately forcing him to fall to his knees. An all-encompassing darkness wrapped around his body, chaotic stars shining brightly as they condensed into black flames.

“W-What the…?!”

He was unable to even react before he was completely trapped inside a strange {Domain} created by Jack and Fenrir.

“Everyone worked hard to protect me; the least I can do is take care of you now that I can move.”

Jack’s bare chest overflowed with black and blue runes, moving around and expanding across his body. Black fur and black crystal spikes grew over his body, his appearance swiftly morphing into that of a giant black werewolf.

“Fenrir, let’s kill this bastard.”

“Sure, I was getting hungry anyway!”

“Y-You…! You’re Jack?! Why are you- So Uroboros lost already?!” Gustavo muttered. “Wait, this isn’t supposed to go like this!”

Gustavo was incredibly dull, and once things didn’t go as his master told him they would, he would fall into a slight panic, incapable of being able to react properly to a situation he could not predict.

“D-DAMMIT! RAAAAHHH!!!”

He let his animalistic emotions take over him as his body turned red in wrath, rushing towards Jack while ignoring the darkness and chaotic stars consuming his body through black flames!

FLASH!

He raised his two gigantic draconic claws, harnessing his Demonic Stigma’s powers and his own Chimera’s abilities into them until they overflowed with a golden aura.

SLASH! SLASH! SLASH! SLASH!

A storm of slashing attacks reached Jack, which would easily tear a whole building into shreds with ease! However, Jack’s body...

It remained unscathed!

“So this is the power of jumping so many Levels… My Endurance is already at the peak of S Rank.” Jack analyzed his strength carefully, speaking with a serious voice, his face showing no emotions whatsoever.

“W-Wha…?!” Gustavo was shocked; his mighty strength seemed like nothing against the man in front of him. “No… This is bullshit!”

He quickly opened his jaws, harnessing his Mana and Demonic Powers, his throat inflating like a balloon as it turned bright red. He unleashed an explosive draconic breath, the beam piercing through the darkness and quickly reaching Jack, who summoned a single black sword.

“{Chaotic Shadow Blade Arts, First Form}: {Crescent Umbral Void}!”

SLASH!!!

A single slash of pure chaotic darkness was released from his sword; it pierced across the dragon's breath and then reached Gustavo!

“U-URGH?!”

The Draconic Chimera experienced utter disbelief as the slash pierced through his entire body, slicing him into two halves.

“W-What just happened?!”

His consciousness swiftly faded away as both of his halves dropped on the floor, blood and guts splattering everywhere.

He died on the spot!

“Well, this power will be hard to control.” Jack sighed. “Now... I better not waste this meal.”

Jack’s arm quickly shifted into countless wolf-like jaws, devouring his entire corpse mercilessly.

Dozens of more notifications popped up as he gained several new skills.

The Domain slowly broke apart as Jack walked outside. He equipped a new set of clothes through his Inventory and saw Henrietta heal the three other Hunters that were holding back Gustavo.

“I-Is that you, Jack?” Hilda asked.

“Where’s Gustavo?” Scarlet asked.

“He’s gone and won’t come back ever again,” Jack said with a domineering tone of voice. “I would love to sit down and talk, but right now, even after what happened, we have little time. My sister is still in danger, and this entire castle’s about to break apart and fall over Stronghold.”

“Y-You’re right, of course!” Scarlet nodded, blushing before Jack’s Aura.

“Let’s go then; I need to know how Kevin's doing!” Henrietta cried.

“Once this whole thing ends, I’m taking some vacations…” Hilda sighed.

“Me too.” Dimitri, who had just woken up, yawned.

.

.

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(Anna’s POV)

The moment I crushed Uroboros' Soul Heart completely, a bright crimson light engulfed me, followed by the Constellation’s screams as he died.

It looks like Jack and Fenrir on the other side managed to deal enough damage as well, making it possible for Uroboros to truly die.

Ultimately, the only fault for his death was his own endless hunger for power; he wanted to devour me and Fenrir so badly that he attempted to descend into Jack’s own body.

But even then, I can’t believe I felt such enormous exhilaration and happiness after this. An event like this never happened in the original storyline.

The defeat of a Constellation in the First Awakening is a big plus! It means that our World will no longer be regarded as a trash world that will be discarded.

And it means we’ll be finally entering the race to join the Realm Beyond, the whole world and all its inhabitants, I mean.

This is a HUGE step for humanity as a whole and just another step in my plan to save Earth, unlike in the original storyline, where Jack and his allies left Earth to be destroyed after it “lost” the competition between Worlds.

This “competition” will become much clearer in the Third Awakening, when Scenarios appear and we finally get to fully interact with other, similar competing worlds.

The worlds we’ve seen so far inside Dungeons are nothing but Abandoned or Fragmented Worlds, victims of having lost this “competition” we are all forced to take part in.

However, it is not like things are done here; I still have to end Beelzebub, and I have no idea what’s going on with Heisenberg and the other Chimeras.

I have to hurry and get out of here first!

Neberius’ Soul Scape was already at its limits, slowly breaking apart.

I better take what I can before leaving, so I can also seal Neberius before he dies! I can’t miss on yet another enslaved—I mean, Death Apostle Friend!

First of all, the Cosmic Soul Fragments.

“W-We truly killed Uroboros?!” Sepa was still shocked by what she was seeing.

“Hahaha! There’s no dragon I cannot slay—not even a snake!” Laughed Gram.

“You two did well; thanks for your help.” I smiled, quickly pointing my hands towards the countless Cosmic Soul Fragments floating in the disappearing Soul Scape. 

My hand absorbed my Cosmic Energy, quickly transforming into a gigantic hand made of stars and cosmic light, which I used to absorb all fragments into my Cosmic Heart Core.

This unique crystal will become the pillar of my Cosmic Energy cultivation, giving me an advantage that no mortal can easily achieve.

But to fully cultivate its powers, I must absorb Cosmic Energy and Cosmic Soul Fragments, and Uroboros left hundreds of delicious pieces all for myself!

FLUOSH!

The glass-like fragments were assimilated quickly, and the crystal replacing my heart absorbed them, releasing a crimson-colored cosmic light from my chest.

I felt its powers coursing through my entire body, constantly refining it and enhancing my entire strength to a completely new level.

And that’s without mentioning the ridiculous quantities of EXP I gained from slaying Uroboros, even in his restrained state!

FLASH!

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