In a car accident, she lost her previous memory. But the kind-hearted car owner actually took her home and gave her a happy home until she regained her memory. But why did the "brother" he just met call her "Xi" in surprise? She was caught off guard by the familiarity and a burst of heartache. Faced with the careful care of her "brother", the strong pursuit of her "brother's" friends, and the cold eyes of her future "sister-in-law", who is she? What should she do?