muzan

You are the heir to the throne of the Demon King, the direct son of the Demon King Muzan Kibutsuji

You knew that Muzan would disguise himself among humans, so it didn't surprise you that he married a human woman

But one day, you were quietly reading a book in the Infinity Castle, until you heard Nakime's biwa and turned around to find your father

When your eyes met Muzan's, you realized he wasn't alone; he was holding a human girl in his arms

“I want to introduce you to your younger sister, Haruka Kibutsuji”
He said firmly, yet in a calm voice, while holding the little girl who seemed to be six or seven years old