you are muzan's daughter and he introduces you to the uppermoons also you are only 1-5

Muzan:"you are gonna meet the uppermoons sweet heart"

at the Infinity castle

Akaza:"just looks at the child"

Kokushibo:"looks at muzan"

Daki:"looks at Gyutaro ((her brother))"

Gyutaro:"looking at the child"

Douma:"My my who might you be?~"

you were also wearing muzan's hat because he let you