When the Lights Fades

Act I, Chapter 1: The beginning of the Downfall

As she hurried to her home, Nezuko noticed little red stains in the snow but didn't pay attention, she thought she was seeing things because she had just woken up but... the stains were becoming more frequent and broader and seemed to come from a direction that Nezuko knew, her home.

'...!' She looked up, a little further away from her, she noticed a dead body, massacred. '...? Gods, don't tell me it's true, I beg you...' She ran towards the bloodied body, disfigured even. First, she saw Rokuta, the youngest brother in the family, his throat slit "N-no... Rokuta!" She checked the body temperature but she already had the answer, a cold body and dull eyes meant only one thing; Rokuta was dead.

She got up and decided to enter the house where the bodies probably were. A vision of horror was shown to Nezuko; his mother, Takeo, Hanako and Shigeru all dead. Their bodies bathed in a large puddle of blood. The World was simply against Nezuko, it wanted her to be drowned into despair but- 'Tanjiro! where is he?!'

She searched for a long time but... no trace of her brother... Her face tensed up, she was angry, she couldn't save her family and her brother was missing, she wanted to– No... She will take revenge on the one who killed her family but the one problem remains; How?

"Your family has been Killed by a Demon, if you want to avenge them, become a Demon Slayer, go to this address and tell him that Tomioka Giyuu is sending you." Said a voice that was next to Nezuko. ' ... ? I didn't hear him-'

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A sound of a Biwa could be heard throughout the Infinite Fortress and all the Lower and Upper Moons were summoned. "Lower your heads and crouch down." Said an authoritarian voice. It was Muzan, the Demons King. The Moons were forced to bow because of his absolute words. "I have called you here not because a Moon is dead as you see it, but because I feel a weak but omniscient presence and I would not tolerate any presence other than mine. It seems to be hiding somewhere and Nakime seems unable to locate it and interfere with its position with her Blood Demon Art. Find it. And when you found it, if it's a Lower Moon, ask Nakime to teleport us to you. Now go." He ordered before a new Biwa sound was heard, and Muzan disappeared from the sight of the Moons.

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After hours of searching, it was Rui, Lower Moon 5 who found the location of the 'presence'. It was in the most hidden depths of the Fortress, hidden by ghost walls and finally, protected by a seal with written "Mugen" on it. Rui called Nakime and everyone was teleported to where he was.

Muzan examined the seal and ordered the Moons to use their Blood Demon Art one by one in order to destroy the seal but failures followed one another, even the Blood Demon Arts of Douma and Kokushibo, the most powerful Upper Moons were ineffective, the seal simply absorbed their attacks as if nothing had happened, which irritated the King of the Demons.

He snapped; " Akaza, do something, anything but do something for fuck sake!" He ordered.

Akaza swallowed his own saliva, not knowing what to do, and he began to gently walk towards the seal and delicately put his hand against it. He wanted to try a passive approach, maybe it would work? A few moments later, the seal began to crack and a broken mirror sound was heard, Akaza had managed to open the seal without any effort!

Once the seal was completely gone, a room was reveled and we could see a crystal protected by a kind of giant tree roots. Muzan and his Moons were advancing into the room and noticed that something, more like someone was locked inside the crystal.

He was a boy with a young appearance, with a unique hair color, from black to red. The boy was also wearing Hanafuda's earrings, and a Nirichin blade was on his belt. Observing the young boy, Akaza had felt for the first time in his demon life, something he didn't know he could feel. His heart had missed a beat.