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

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Before everyone's eyes, the Nightmare Demon King, the strongest Nightmare Demon in this world, was defeated. His heart pierced by Maria's spear, she devoured his powerful Nightmare Heart, preventing him from regenerating ever again. His Nightmare World proved useless against Maria, who was a terrible matchup for him. The Nightmare World rapidly began to fade, and the Nightmare Demon King's body slowly turned to ashes, his heart no more.

"I'm… dying…?"

His eyes widened as he watched his body disintegrate… After dozens of loops where he triumphed, overwhelming and destroying every foe, the Nightmare Demon King was defeated, and Maria hadn't even needed to evolve to do so.

"This is death. As you said before, death is the only certainty for all living beings."

Maria withdrew her black spear from his chest, his blood dripping onto the floor of his collapsing Nightmare World, which was crumbling and vanishing. Half of his body had already become black ashes.

"But I am… I am death…"

"No, you're merely a Nightmare Demon born from the Fear of Death."

"A-Aaah…! AAAAHHHHHH! I DON'T WANT TO DIEEEEEE!"

The Nightmare Demon King screamed in horror, fleeing from Maria as his body disintegrated further, only a tenth of him remaining.

Maria observed his hopeless struggle from afar. A being of his caliber crying like this… It was truly pathetic.

"You don't know…! YOU DON'T KNOW WHAT'S DOWN THERE…! ONCE I DIE…! THAT WILL EMERGE…!"

"Oh?"

"What I've been trying to keep sealed this entire time…! IT WILL EMERGE AND DEVOUR ALL OF YOU! NOT EVEN THE WORLD WILL SURVIVE! THIS PLANET… IS NOTHING BUT AN EGG FOR IT! AND YOU'RE NOW TRIGGERING IT TO HATCH!!!"

"I know."

"W-Wha…?!"

The Nightmare Demon King's head was all that remained, floating as he faded.

"I know there's a hidden boss down there, the true origin of all Nightmares in this world, and that, indeed, this entire world could be considered its egg."

"And yet you…! You think you can stop it?!"

"I have to try, or else all of humanity will be destroyed either way."

As Maria responded with conviction, the Nightmare Demon King's last crimson eye glared at her in disbelief.

"Don't worry, I'll take care of this world you wanted so badly for yourself. Leave it to me."

"You're… crazy…"

As he fully vanished, the Nightmare World dissipated completely, and Maria stood resolute. Her Evolution was halfway complete, she could feel it, and Lucifer seemed to be in the final stage of his evolution as well.

Yet the entire problem was already resolved!

"Maria, you did it!" Emeraldine cheered. "You're so strong!"

"That was amazing," Jonathan nodded. "The Nightmare Demon King is no more!"

"So that's it, huh? Pretty easy, all things considered!" Partner said with a relaxed smirk. "Shall we go back to the surface now? I want to eat something…"

Maria descended toward the Castle, glancing at everyone. Most of the Nightmare Demons had been slain, though she could still sense a few lurking and crawling in the shadows.

They were filled with disbelief at what they witnessed. The entire world changed forever in that moment, their glorious King dead.

"T-The King is dead…"

"This can't be happening…!"

"W-What… What do we even do now?!"

"No, this is impossible! It can't be happening…! No!"

"Your majestyyyyyy!"

"He was… a weakling in the end?!"

"What do we do now?! Do we fight to the death, or do we surrender?"

"She's… invincible!"

The surviving Nightmare Demons were stunned, unable to believe their eyes. The only human among them stood in silence, equally shocked.

"Is this… real? Did we win? The future… the King is dead…!"

She began crying, slowly approaching Maria, Arthur, and the rest of their group. No Nightmare Demons dared to stop her, too terrified to even be noticed.

"My sister's efforts… her sacrifice, was it not for naught?"

As she looked at Maria and Arthur, they noticed her. Arthur was stunned, though Maria seemed unsurprised to find her here.

"Y-You're…?! Amelia?! What are you doing here?! You're walking?!" Arthur exclaimed, still in disbelief.

"You… You did it…" Amelia muttered, moving toward them. "You actually… did it… you did what nobody else could…"

"…" Maria approached her, gently patting her shoulders. "So this is what you've been doing all this time, huh? I knew there was something unusual about you. Amelia, when did you become the Demon King's ally?"

"This… loop…" she murmured. "I betrayed humanity. I gave him all the information I could… I did… terrible things. I wanted my sister's suffering to end…"

"Your sister's suffering?" Maria asked. "I see. So you never saw us as your siblings. You remember the loops as well."

"She does?!" Arthur exclaimed, while the others were equally shocked.

Meanwhile, Sofia, Alma, Emily, and Martina stood confused, unsure of what they were even discussing.

"I do…" Amelia said. "Although my Dream Heart has Cancer, my Dream Weapon never vanished. The Cancer, in a way, boosted its power but also warped it, making it uncontrollable. It's… the same power my sister had, the Twin Hearts of Time."

FLASH!

Half of a heart made of glass with sand inside materialized, resembling a half-heart-shaped sand clock, glowing with silver light. The sands shimmered back and forth, twitching and glitching.

"My sister… she, whose true name I can't even recall, the one you're replacing," Amelia said, shedding a tear. "She has the other half and shattered it in the first timeline, sacrificing herself to revert the world a week before its destruction."

"I see…" Maria finally understood the truth. "But that power… it didn't last long, did it?"

"No, and with each loop, I forgot more and more about her…" Amelia cried. "I don't even remember what she looked like. I don't even know her name! And with each loop, some of those who died, her closest friends, never returned, erased and replaced by you… the Otherworldlers."

"W-What?" Alma gasped. "W-What's going on? Otherworldlers?"

"Hey, I don't really get it! What is she even saying?" Emily asked.

"Isn't she a human? Wait, no! I recognize her, that's your sister!" Sofia said.

"…" Martina remained speechless, unable to grasp where the conversation was heading.

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