My Vampire Little Sister

The fight with Cthulhu continued for a full half hour. Each time the Demon Lord seemed to recover from my attack, I would launch yet another meteor into its face. And if one meteor didn't work, I sent two hurling down from the heavens. And if two didn't work, I would send four. And if space rocks couldn't do enough damage, I would cast an assortment of spells, from blazing hells to lightning bolts of pure destruction.

Whatever I did, I ensured that Cthulhu didn't have a single second to breathe easily. Flames evaporated its water, and its slimy skin had been perpetually burnt. Through magic, the Demon Lord could recover its injuries instantly, but with each passing spell, the regeneration took a tad bit slower.

My plan was working. Even as a Progenitor, I wouldn't be able to constantly regenerate if my body was incinerated every few seconds. Still, there was a reason why Cthulhu was undefeated throughout its many years of invading our lands.

After thirty minutes of one-sided combat, the Demon Lord retained about seventy percent of its magic power. Even after I'd thrown the entire asteroid belt onto the massive beast, it could still retaliate and constantly damage my Aegis barrier. If Cthulhu were on its home planet, my plan of attrition would likely fail as it could recover its lost magical power from the oceans it called home.

As for why I could continue casting spells without falling into complete exhaustion…

"Jin! How are you holding up?"

"I'm fine… Can the World Tree keep up with my magic?"

"Don't worry about me! Even if you cast a million more spells, it will only be a fraction of the magic pool!"

Sora, who had sensed the immense magical battle from the Elven Forest, rushed to my location and connected my soul to the Spirit of the World Tree. If a Demon Lord was a spawn of the Demon Realm, the World Tree was the avatar of the planet we call home. The magic power it had was bottomless, and not to mention, it could constantly recover from absorbing the planet's energy.

Therefore, my connection with Sora gave me an infinite magic power to draw from. Even after endlessly throwing spells that could destroy entire countries, I'd barely used even a percentage point of the World Tree's energy.

"I'm just worried if your body can handle it!" Sora questioned me with a concerned tone. "Casting so many spells that cost this magic power must have put a strain on your body! Your vessel may be strong, but it's best not to push over your limits."

"..."

I frowned and looked away from the pesky little fairy. Sora was right. I was fine now, but if this battle of attrition continued for much longer, I would have to be careful about pushing my body to the limits. And the even bigger problem was the state of my surroundings.

The Mahayana desert was unrecognisable. It no longer had its signature sand dunes or dry, temperate air. It was still a wasteland, but a whole different kind. Craters upon craters littered the ground. Sand had turned into glass after coming in contact with the intense heat I'd generated, while the contrast of humidity created an updraft of cataclysmic winds.

The battle between Cthulhu and me was violent enough to completely wipe the largest desert in the world off the map, and we were only just getting started. While the planet could survive even if I summoned a million more asteroids, it would make life virtually uninhabitable.

I had to limit the destruction.

"Sora, how far can your connection reach?"

"Hmmm? Why? Are you planning on switching locations again?"

"Yes," I nodded. "Cthulhu still has seventy percent of its magic power. If we continue our battle here, the destruction will creep into the adjacent countries and likely cause irreversible damage."

"I see…" Sora thought about it for a few moments, and eventually, she asked: "So, where are you planning to bring it?"

I smiled and pointed my finger up to the heavens. Understanding my meaning, the fairy widened her eyes and shivered:

"You can't mean…"

"Yes, I'll bring Cthulhu to Outer Space."

"You're crazy!"

Sora spouted before finally coming to her senses. She knew all of my reservations and the damage Cthulhu and I could do to the planet. Therefore, she reluctantly gave me her calculations.

"I've never tried it, but as long as I can feel the Earth, I can channel magic from the World Tree to you. As for how far it can go… Maybe the Moon?"

"Good enough."

Humanity may be unable to breathe or thrive in Outer Space, but Vampires were a different story. As long as I protected myself with a thin layer of magical coating, I could fight perpetually in the vacuum of nothingness. As for whether Cthulhu could do the same… Well, let's find out.

"Hey, Cthulhu. Let's stop this farce, shall we?"

"... What are you planning?"

"You know… I've always wondered. Can an octopus swim in Outer Space?"

"..."

I raised my arm up and injected magic power into my middle ring. Azure light warped the Demon Lord and me as the world around us distorted. Cthulhu attempted to escape by flying up high, but he couldn't outrun the power of Space itself. In less than a nanosecond, the two of us were transported from the desolate, broken land of the Mahayana desert to a black realm of nothingness.

Celestial objects surrounded us on all fronts. In the distance, a blue glow was emitted from the planet I call home. Behind it, the lunar body that all tides and oceans relied on radiated with a mystical light. Even further from it, multiple planetary bodies orbited around the central ball of light and warmth all Vampires dreaded.

Protected by Aegis and a magic coat, I could withstand the UV light from the Sun and remain unharmed even in the vacuum of Outer Space. I didn't feel encumbered at all, given that I was over three hundred thousand kilometres from the planet.

No, in more ways than one, I felt empowered by the emptiness of Space. I no longer had to care about protecting the environment and could finally go all out.

"Sora, how's the connection?"

"It's there… But why didn't you go to the Moon instead? I could get a clearer reception if we were orbiting Earth?"

"I can't risk destroying the Moon as well, right?"

"... You monster."

Barely a year ago, I could not move my body without the help of my parents. Yet now, my strength was dangerous enough to warrant the worry that I would destroy the Moon.

"... You brought me up into Space."

Cthulhu's disgusting voice sounded in my mind. Like me, the Demon Lord had protected itself through a thin layer of magical coating, allowing it to move in the vacuum of Space freely. Perhaps it was its endless years of experience, but it didn't show any signs of weakness or expose any of its vulnerable points. Even in this unforeseen circumstance, Cthulhu could remain as calm as it was on Earth.

"If we continued our battle on Earth, I would have destroyed the continent before I killed you."

"... Do you really think you can kill me?"

"After going through all that, you still doubt my power?"

"... No," Cthulhu shook its head. "... I'll admit it, the Goddess was right about you… If we leave you alone, your existence will be the bane of our race."

"Hoh? So your Goddess saw my future, huh? I wonder if she foresaw your death too?"

"..."

The Demon Lord remained silent. Its menacing eyes shone with a furious glint, and its waving tentacles wiggled angrily. Unable to hold back its rage anymore, Cthulhu emitted much magic power, far beyond anything I'd experienced from the monster.

Black goo exploded from its aquatic body as the Demon Lord underwent a physical metamorphosis. Warped in its grime, Cthulhu remained in a cocoon without doing any damage to me. Usually, due to my morbid curiosity, I would be tempted to let Cthulhu go through his change. However, I had an uneasy feeling about the Demon Lord's actions.

Raising my hand straight at Cthulhu, I channelled a large amount of magical power into my ring of Creation. Rainbow light erupted from my thumb, and the radiance blinded me completely. However, I didn't need my eyes to complete the spell. More and more magic power was spent by both the Demon Lord and me, creating two distinct auras illuminating space's darkness.

Alas, no matter what Cthulhu was planning, it was far too slow. With my magic power at its peak, I cast the spell that I could never conjure up back on the planet.

"Genesis: Sun."

A miniature Sun appeared above the black cocoon, and gravity forcibly pulled the Demon Lord into its surface. Solar flares ripped the goo from the monster, as its body melted like an ice cube on a hot Summer's day.

The Sun I'd created was infinitely smaller than the one at the centre of our solar system, but it possessed enough power to run a million nuclear plants. No matter how physically superior Cthulhu was, it couldn't resist the spell completely unharmed.

Or so I'd thought…

BOOOOMMM!!! ????????????r????????????. ????????????

The flaming star that stood independently in the emptiness of Space exploded into a pile of stellar residue. A solar flare far beyond the ones I created attacked my Aegis barrier, shaking my defences and pushing me hundreds of kilometres back.

However, I didn't mind the damage one bit.

Why?

My eyes were on the disgusting being that broke free from the black cocoon mass.

Black tentacles which coiled like satanic serpents… A mass of rubber, scaly meat ten times larger than any mountain I'd ever seen… Draconic wings that spread just as wide as the world's biggest lakes…

Ah, how could I forget?

The original myths of Cthulhu didn't start with it being the Matron of the Seas… Cthulhu was originally…

A cosmic horror.