The Zhou family has high hopes in giving birth to a son, but was disappointed when Zhou Ji Wei was born a girl, making her the third daughter in line. Because she was a disappointment to the family, she was only ever given hand me downs from her sisters. She felt no love from her family, but luckily she feels the love of a family from her neighbor especially Dai Nai Nai. There she meets her 'brother' Dai Yao Qi and follows him around trying to be the best sister ever, however he has never wanted to have a sister. As she tries her best to be close to him as his sister, she slowly realizes the feelings she holds for him are not love for a brother but something more.
