After a car accident, Lu Miao gains a new older brother, Jiang Haoyue. A martial arts enthusiast, she becomes his protector, while he stands by her in his own way. As they grow up, Lu Miao’s feelings for Jiang Haoyue evolve from sibling affection to something deeper. When a new student, Shi Che, enters their lives, it stirs jealousy and uncertainty in Jiang Haoyue, leading to a shift in their bond from sibling love to young romance.