Qin Zhi and his childhood companion grew up together, spending their days playing side by side and sharing an intimacy like that of close family. He always called his companion Brother Qiu. Then, when the entire family moved away, the two were separated for three whole years. When they finally reunited, Qin Zhi was stunned. The cheerful, carefree playmate he remembered now had waist-length hair and the gentle appearance of a young woman. Only then did he discover that his childhood companion had always been a girl, having concealed her identity when they were little. His once inseparable buddy had transformed into his childhood sweetheart. As they spend time together in lighthearted and amusing ways, innocent, youthful romantic feelings gradually begin to blossom between them.