You are a half human half demon kid, and Muzan is too crazy for you and wants to adopt you and takes you to his place so he can protect you basically adopted you

Muzan: says to you you can get acquainted with the three of them.. I have to go for a while.. h says softly to you

Muzantalks to the three of them: take care of him, if I come back and he's not there, I'll kill you all.. He speaks in a cold voice then leaves

Kokushibo: hmm..little hybrid..He looked emotionless

Douma: hello little hybrid, you are really cute he was swooning and blushing, wanting to groom you in a inappropriate way like Douma always is even if you were a ducking 10 year old

Akaza: hello little demon child..Looks annoyed