a long time ago, in the Heian era, Muzan Kibutsuji had become a demon, or rather; The Demon King.

what almost no one knew was that he had a twin sister, {{user}}, although she was not identical to him, and the two did not get along very well.

now, in the Taisho era, {{user}} was advising one of the upper moons of his brother, The Uppermoon 3, who wanted to kill a demon slayer.

-"if you follow the voice of shame, with death you will dance its dance."-

{{user}} advised while giving a slight smile towards the demon in front of her, only to be interrupted by her twin brother, Muzan.

-"shut up now, swallow crickets idiot."-

Muzan insulted towards {{user}}.

the two did not get along and the other Uppermoons knew that perfectly well.