Reborn As A Ghost: Time To Build My Undead Army!

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"That's right, she's my sister..." Maria sighed. "Or rather, we are supposed to be siblings... This is the truth, Alma, Emily, Sofia, Martina... all of us are not from this world."

"They're... the people they replaced are long dead, forgotten. The power that regressed this world seven days with each destruction had repercussions in this world. It erased our memories of my sister and those closest to her," Amelia explained. "Their memories were fully wiped from the world, leaving vacant spaces for souls from another world to replace them. Sent by whom? Not even I know."

"E-Eeeh?! So she's not the real... What?! I don't get it! Maria...! Maria is the real Maria! R-Right?" Alma cried, glancing at Maria.

"My name is indeed Maria, and who I have shown to you this entire time... is my true self, Alma," Maria said. "I truly do love you... but she's not lying. I don't belong in this world and arrived here only seven days ago. I replaced a nameless person whom this world no longer remembers. She sacrificed herself for this world, using her powers to loop back seven days in hopes of saving it, so people could change its fate."

"E-Eh...?" Alma's eyes widened. "I don't like this prank! W-We just won right now, right?! S-So why even go this far to say such weird, incomprehensible things?!"

"They are not weird or incomprehensible, but I understand if you don't want to believe them..." Maria sighed. "I just want you to know this is the truth."

"So we've been lied to this entire time by complete strangers?!" Sofia asked. "What kind of bullshit are you talking about?! You're Maria! Everyone knows it's you. We have memories of you! And those memories, at least for me, are real!"

"Yeah!" Emily said. "Like, does it even matter whatever you're saying anyway?! We won!"

"..." Martina didn't know what to say, remaining silent.

"Is that true?! Nyx?! Emeraldine!" Alma kept crying, asking them, hoping they were joking.

"Yeah... Sorry Alma..." Nyx nodded.

"We come from a world called Yggdrasil," Emeraldine said.

"My sister..." Amelia sighed. "At this very moment, she must be slowly dying... I don't know where she is, but I can feel it. We've always been connected."

She gazed into the dark depths of the Nightmare Void.

"Please let me join her..." Amelia sighed. "This world has been saved, but without my family alive anymore, without my friends... I cannot find a reason to live."

"I can't let you do that," Maria said, grasping her arm. "I am sure your sister wouldn't have wanted that, Amelia."

"What do you even know about her?! You just replaced her! You're not her! You doppelganger! Why?! Just why is your face... your face reminds me of her, your voice...! Even your name, though I know none of those are the same as hers!" Amelia roared angrily, struggling to free herself from Maria's grasp but failing. "Let me go! Let me go already! I don't want to live anymore!"

"No..." Maria stepped forward, embracing her tightly. "Even if I am not your real sister... I will care for you and protect you like one. This is the promise I made to her, to your sister, who sacrificed everything for you and this world... I am sure she wouldn't want you to die, right?"

"A-Aah... Just... just let me go... Please..." Amelia wept on Maria's shoulders. "I miss my sister...! I want her... and my brother...! Why... Just why... did they have to leave me behind?!"

As Maria comforted her with an embrace, Amelia poured out her pain and sorrow. Everyone remained silent. Even Alma, realizing the gravity of the situation, fell quiet, lost in thought.

"What... what can we even do now...? Those we lost... will remain lost..." Amelia cried. "Even if the Nightmare Demon King is gone... I-"

"It's not over yet, Amelia," Maria said, meeting her eyes. "Perhaps we cannot bring them back, but this world... we can save it for real now."

"For real? What? What are you talking about?! You already killed the strongest monster! The Nightmare Demon King was-"

RUMBLE!

A sudden tremor widened everyone's eyes, putting them on high alert. They glanced around. The Nightmare Demon Castle shook, as did the entire nightmare dimension.

And the void sea below!

The liquid void miasma bubbled, and countless crimson lights surged from its depths.

The tremors intensified as Alma and her friends panicked, while the others, though vigilant, sensed what was coming.

"W-What's going on now?!" Alma asked, desperate for answers.

"I don't know! Weren't we done here?!" Sofia asked.

"No, we are not done..." Maria said. "The true enemy, the real final boss, is coming. Just as the Nightmare Demon King said, with his death, he would finally awake."

SPLAAASH!

The Nightmare Void Ocean erupted as countless long black tentacles emerged, covered with crimson eyes and sharp, fanged jaws.

The massive tentacles coiled around the Nightmare Demon Castle, enveloping it tightly as crimson eyes pierced their very souls.

"YOU'VE DONE WELL, OTHERWORLDLERS."

A powerful voice reverberated through their souls, sending shivers down their spines and forcing most to their knees.

"Aaaggghh!" Sofia screamed in agony, clutching her head as it felt about to burst.

"W-What's that?!" Emily cried, blood streaming from her eyes.

"M-Mariaaaaa!" Alma wailed as Maria held her in her arms, shielding her from the overwhelming pain.

"Uuuggghh!" Martina vomited at that moment.

"Calm down," Maria said, her Aura enveloping everyone, shielding them from this eldritch abomination. "This is the real final boss."

"NOT ONLY WERE YOU ABLE TO STEAL A FRAGMENT OF MY OWN POWER, BUT YOU WERE EVEN ABLE TO DEFEAT MY PAWNS. YOU'VE DONE WELL! AMAZINGLY WELL!"

The monstrous, distorted voice echoed everywhere, causing headaches despite Maria's protection.

"W-Wha...?! What is that thing?!" Amelia fell to her knees, utterly shocked.

"This is the true monster your sister was protecting this world from..." Maria said. "This world, the Azure Star, is his egg. He's what you would call... an Outer God."

And he bore a simple name and title.

"The Original Nightmare Curse."

The primal curse that birthed the Nightmares and all derived from them, even the Nightmare Demons.

"THIS ENDLESS LOOP ENDS TODAY. THIS WORLD, MY EGG, SHALL HATCH. AND ALL OF HUMANITY WILL PERISH WITH MY BIRTH!"

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