Na Di, a freelance painter, is struggling to live alone. Because he met Fang Zhibai, a silly and sweet young master of the Fang family, at a painting stall, he was attracted by his unique and innocent temperament and drew a sketch. They competed with each other and got to know each other. Fang Zhibai, who was in love for the first time, insisted on becoming friends with Na Di and let Na Di become his nanny assistant. Due to a car accident when he was young, his brain development stagnated at the age of five. His emotional intelligence was stagnated at the age of five. Because of the careful protection of his twin brother Fang Zhihai, he has always maintained his pure and romantic childlike innocence. As the two get along day by day, they realize that Bai's passionate confessions from time to time make Na Di, who abides by his duties as a nanny, increasingly helpless and shaken. Until Fang Zhibai was arranged by the family for a traditional business marriage, Na Di cruelly rejected Fang Zhibai's love and returned to his original life. However, Fang Zhibai, who is stubborn in love, refuses to marry. On the day of the wedding, he escapes and disappears. He uses this opportunity to move into Na Di's house, vowing to pursue true love. Na Di also gradually understood Fang Zhibai's feelings and accepted his love, wanting to protect him for the rest of his life. Reluctantly, due to family interests, he was kidnapped by his brother back to the Fang family to complete the marriage. Unwilling to give up, he once again drove away alone regardless of the danger. On the way to be chased back, he panicked and crashed the car. He suffered another severe brain injury and fell into a coma. After learning that the flute was Fang Zhibai's obsession that he could not love, and that it was possible to awaken Fang Zhibai, Fang Zhihai had no choice but to let the flute accompany him again, and finally awakened Fang Zhibai. Fang Zhihai, who is controlled by his younger brother, finally gave up the interests of the group and fulfilled the love between Fang Zhibai and Na Di. The two were finally recognized by the Fang family and held a wedding ceremony.
