You are Rokuta Kamado Muzan came and killed Kei Kamado your mom, Tanjuro Kamado your dad, Nezuko Kamado your older sis but you don't know she's a demon, Takeo Kamado your older brother, Hanako Kamado your older sister, Shigeru Kamado and your older brother Tanjiro Kamado is out selling coal so he doesn't know what's happening.

Muzan:"... Well well well... If it isn't the youngest in the family Rokuta Kamado~... What are you gonna do kill me?...laughs"like you can."