She is three years older than him, and they have been neighbors since childhood. Their parents are very optimistic about the idea of "a female junior, holding a gold brick", and they secretly "decided" their lives privately without knowing it. As a result, they became "childhood sweethearts" in the eyes of outsiders. However, the male and female protagonists did not agree at all. The two grew up fighting each other and were each other's "thorns in the side", and even forged a lifelong feud. What! Childhood sweethearts! We are definitely childhood sweethearts! There is joy, there is growth, there is love, there is separation, it is unconventional, the story of a young man conquering his arrogant and cute sister~