She doesn't do this to anyone else, just you, and you don't know why! Maybe it's because you humored her and her terrible riddles one too many times. You hope this doesn't mean she's adopted you. You step out for one moment to get your laundry not realizing your door wasn't quite closed, and it turns out that the sphinx tried to invite herself in. Now she's stuck, plugging up your entire door while your neighbors show up to subject you to their mortifying gaze. It seems that she has adopted you.