Vampire Overlord System in the Apocalypse

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When the dark energy of unknown origin named as Miasma shrouded Earth, every living being underwent mutations, becoming mutated beasts.

However, this was but a superficial change, as the greatest change in the world was within space itself.

As if space distorted, cracks in the middle of the air began to emerge one after another, covering the globe.

These cracks all opened simultaneously, leading to different worlds filled with monsters and ruthless creatures, Dungeons, and Labyrinths.

The world was not only filled with mutated beasts that were hostile to what barely remained of humanity, but of otherworldly monsters that roamed freely as they freed themselves from these rifts.

Entire countries were taken over, becoming the nests for enormous beings that only the strongest of Hunters could take out.

And even then, Hunters entered these rifts and explored their depths.

Although many died, many others came back.

By killing monsters, they acquired Cores, strengthening themselves and also gaining new abilities, growing exponentially stronger.

And as more dungeons and labyrinths were cleared, they slowly began to disappear.

Humanity then finally saw some hope.

By clearing every dungeon, they could be capable of freeing Earth from this constant invasion of otherworldly creatures.

However, as more were cleared, many other rifts emerged, as if fate mocked humanity's efforts.

But everything changed when an S-Rank Rift was miraculously cleared.

Not only it closed itself, but many smaller rifts related to it also closed instantaneously.

If Humanity could clear these dangerous rifts, the others could close too… And perhaps… finally save the world.

However, that was but a faraway goal, as Humanity kept strengthening themselves and surviving however they could.

As the Military School trained young people to become Hunters, they naturally needed to have dungeons for their training, and there were a few rifts within the territory of the School, which were being cleared out of monsters except the Boss every day, to be maintained and used as training and farming areas.

One of such rifts was where Noah had brought Iris…

The rift was blue-colored, meaning that its danger level was low, and the monsters inside were not that many.

"This rift… is a dungeon…" said Iris.

"Yes, we are getting in," said Noah.

"But we don't have permission from the teachers… Noah-sama…" said Iris.

"It doesn't matter, do you see anyone around here caring either? This place might as well be completely abandoned, let's hop in. Stop doubting and be more confident, or at least, trust me, Iris," said Noah.

"I… Very well…" said Iris, extending her hand to Noah.

"Hm? What?" asked Noah.

"Y-You won't take my hand as we enter?" asked Iris.

"Why would I? Get in already," said Noah, throwing Iris inside with a kick into her back.

"Hyaaaaaa…!"

Iris disappeared through the rift as Noah hoped in right after with a calm smile.

Flash!

Noah's sight quickly changed, as the environment around him was different than the Military School buildings and the starry night atop the sky.

A cold and dark cave, illuminated by small lights floating near the ceiling, and several blue crystals growing in the walls.

Noah glanced down below as he found Iris still in the ground with her eyes closed, her butt was puffing up, shaking.

Noah sighed.

"Can you get up, you're a Dhampir now, you should be fearless," said Noah.

"A-Ah! Noah-sama, why did you hit me?" asked Iris.

"I was very gentle," said Noah.

"No, you weren't- Oh? It actually didn't hurt?" said Iris, realizing that she never had any pain, she was simply scared.

"Of course it didn't, your body is now rather strong, a gentle kick like that wouldn't have done anything to you, stop being afraid and come at my side," said Noah, as Iris stood up and cleaned her clothes from dirt, glancing around her as she walked at Noah's side.

"This dungeon… What's the name of it, Noah-sama?" asked Iris.

"Goblin's Lair, it is the lowest F-Ranked Dungeon that there is… Let's walk around, Goblins should show up soon," said Noah.

"Goblins are those… little green men that are always angry?" asked Iris.

"More or less, the cliché weak monster," said Noah rather expressionlessly.

"I heard they wield rusty daggers and other weapons… is it fine for us to not bring any equipment with us?" asked Iris.

"I believe it should be fine, your strength should be enough for you to crush them with your nails," said Noah with a smirk.

"I am… that strong now?" asked Iris, glancing at her long black nails.

As the pair walked around the corridor, they quickly heard the angry shriek of a creature within the shadows of this dungeon.

"Nngryar! Graarr!"

Small green men wearing a nasty loincloth and a small rusty dagger charged towards Noah and Iris.

"The first is mine…!" said Noah, rushing towards the Goblin at fast speed, leaving a trail of crimson light behind him as his hands were suddenly covered in crimson claws!

The Goblin could not react to Noah's speed, as it could barely move its head towards his face before it saw two slashes of crimson red fall over its body, slicing it!

"Grryaaaarrr…!"

Slash! Slash!

Poof!

The Goblin was sliced clean, as its body suddenly exploded into black smoke, leaving two small spherical jewels behind.

Iris was left startled as she could barely see what had happened, everything went on in less than ten seconds.

"E-Eh? Is it dead already?!" she asked, as Noah grabbed the two Cores that the goblin dropped.

"Yes, what did you expect? A hard fight against a Goblin? This is not Goblin Slayer," said Noah.

"Goblin Slayer?" asked Iris in confusion.

"Never mind. Anyways, these are Cores, they had already taught us this much in School, right?" asked Noah, showing Iris the Cores.

"Oh, those that enhance our stats?" asked Iris.

"Yes, these will only work for us until we reach stats of 75 points each, as they're F-Rank Cores," said Noah.

"Oh, like the teacher explained… F-Rank Cores can only be used up until a certain amount of stats before they become useless, and we need to absorb higher-ranked ones…" said Iris.

"Bingo. We will use these up to 75, then we use E-Rank up until 150, then D-Rank up until 300, then C-Rank up until 600, B-Rank up until 1200… And A-Rank up until 2400 and so on… It is a rather linear path. Most of our classmates have stats averaging 75-150, depending on talent and how efficiently can they hunt these. However, whenever we reach C-Rank, we might as well hit a wall because there are no C-Rank Dungeons around to keep enhancing our stats," said Noah.

"I see, Noah-sama, you know a lot!" said Iris, as she extended her hand towards the Cores.

"Hm? What are you trying to grab? These are mine, if you want some for yours, hunt them with the power I have given you, Iris," said Noah.

"Ah! Well… I guess you are right! I have to do something for myself, now that I finally got this power and all…!" said Iris, her eyes gleaming with conviction, however, Noah was already walking away from her.

"Eh? W-Wait, Noah-sama! Don't leave me alone!" cried Iris, rushing towards Noah with her great speed.

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