Ai Xi, who went to Spain to study abroad, encountered a robber on the streets of Barcelona. Fortunately, the mixed-race teenager Qian Jin came to help. The two made an appointment to meet in the park. Unexpectedly, Qianjin was retaliated by the robbers and had her head broken and was sent to the hospital. Ai Xi waited in the park for a long time, but did not see Qian Jin and left lonely. After returning home from the trip, Elsie learned that her father was remarrying and that she would soon have a younger brother. Unexpectedly, her future brother turned out to be Qian Jin, a mixed-race boy she met in Barcelona. While living together, the two gradually realized that their feelings for each other were not as simple as brother and sister. In order to maintain family harmony, Ai Xi has been pretending not to be aware of Qian Jin's feelings for her, but Qian Jin always challenges her bottom line.
