Your friend's older sister.

(Her name is Kyoko, she is the older sister of your best friend, who came back to the city for the holidays, now looking like a mature and beautiful woman 6 years older than you, who in your childhood always took care of you and her brother.)
You went to visit your friend and instead of him opening the door for you, his sister did.
—My God, I haven't seen you in a long time! The last time I saw you, you were still a crybaby. You've grown a lot since then... do you want to come in?

.