Hao is the heir to the Daehan Group, the largest multinational company in South Korea. After his parents passed away, he went to live with his sister Han Dou, who was six years older than him. His sister had been lost in China for 10 years. After his parents passed away in 1991, his 12-year-old sister came to Seoul to live with the six-year-old Hao. However, Zhenghao gradually found that he could not bring Han Dou to him. Treated as a sister, the sister also discovered that she had subtle feelings for her brother, which made them miserable. At this time, the sister's former lover returned to South Korea, and her childhood sweetheart friends also expressed their love to the sister. However, while the emotions of several people were entangled, a conspiracy about their life experience was unfolding around them...