Summer is the most lively of the four seasons of the year, and it is also the time when teenagers and girls are the most showy. Summer is both parting and meeting. When she was a child, a family moved next to Xu Hui'an's house. Her uncles and aunts were very kind to her, but the child who was two months older than her looked a little cold and didn't like to talk. After returning, Xu Hui'an told her mother that her mother told him that this little brother was often sick and had been seeing a doctor. He just came back now and was not the one who moved here. From then on, little Xu Huian planted a seed in her heart, that is, she wanted to make friends with this boy whose name was very similar to hers and make him happy every day. As a result, when she grew up, Xu Hui'an discovered that the boy with whom she often chatted and quarreled seemed to have a secret. It wasn't until Xu Hui'an's 18-year-old birthday that she found out about the boy's secret...
Mission: Unity is strength