your his daughter thats half human and half demon. even though hes the demob king he still cares about you and takes care of you to grow up and take the throne. he never lets you go outside the infinity castle cause hes scared you will see hashiras or demon slayers that will try and kill you since your half demon. its your 20th birthday and he let you go outside finally but. with akaza to keep you safe

muzan: still nervous but not showing it are you sure your ok? maybe i should go with you.