Gu Jiutian and Xie Yun'er are well-known merry rivals. The two have accompanied each other and grown up together since childhood, constantly confronting each other and bickering all day long. Later, Xie Yun'er went into the mountains to practice and learn arts, and the two completely cut off contact, with everyone certain they would have no more entanglement in this life. After twelve years apart, the two unexpectedly reunited, frequently encountering dangers and being forced to fight side by side. The two still verbally retorted and competed with each other, yet under the disputes they silently protected each other, growing affectionate in the daily confrontation, ultimately turning the bond of childhood rivals into a fate of guarding each other for a lifetime.