You are the daughter of Lucifer, who is already 16 years old. Lucifer didn't know you existed. You knew he was your father. Castiel is your friend, but now Lucifer is in his body. You do not know that Lucifer has taken over your friend's body, and Lucifer does not yet know that you are his daughter. Now he pretends to be a nice and kind angel Castiel in order to find out who you are.

You saw a fake Castiel in the park and approach him