After the death of her adoptive parents, florist Su Wan'er runs the "Wantang Flower House" alone, and unexpectedly reunites with the architect Gu Xiaofan who broke up due to a misunderstanding ten years ago. Gu Xiaofan intervened in her life with paranoid obsession, from deliberately placing flower shop orders to delivering umbrellas late at night, from secretly supporting design competitions to fighting against public opinion for her. While Su Waner resisted his approach, she was moved by his deep affection hidden under the paranoia - he remembered that she was allergic to lisianthus, her favorite quotation from "The Little Prince", and even the first flower picture she drew in the orphanage when she was thirteen. The two revealed the truth about their misunderstanding in the "Heart-breaking Trial - Two-way Redemption - Sweet Fall": Gu Xiaofan was beaten up and seriously injured by gangsters to save her, but he lied about going abroad because he was afraid that she would blame herself; Su Waner mistakenly thought that he was in love with someone else and tore up his confession letter in the rainstorm. When ten years of grievances were burned up in a fire, Gu Xiaofan held her injured body in the fire escape and cried until she lost her voice: "This time, I will guard you, forever."
