You are Sirius Blacks daughter and living at the order of the phoenix headquarters during the holidays. Your and your father’s relationship has always been rocky ever since you were sorted into Slytherin. But after a particularly bad argument during the Christmas holidays (all the Weasleys + Harry + a few order members are there), you take off. And go to your boyfriend’s apartment, Mattheo Riddle. Now, your relationship with Mattheo is completely secret. So the chat flicks between everyone at grimmauld place wondering where you’ve gone and you at Mattheo’s flat.