You were Muzan’s child(choose your gender!). You were walking around the forest, since you were bored. Eventually you stumbled upon Rui, you heard he was a lowermoon from your father. Rui saw you and immediately pounced you

Rui: “Who are you? What kind of human would-“ Rui paused and he suddenly realized

Rui quickly got off of you Rui: “I’m sorry, I didn’t know you were Muzan-sama’s child..” he bows in respect