Luo Mengmeng and Shen Muzhi have lived together for fifteen years since childhood. They are five years apart and they are childhood sweethearts.
When Shen Muzhi was eighteen years old, he joined the army according to Mr. Shen's wishes. He and Luo Mengmeng had not seen each other for almost five years. They originally thought they were brother and sister. As Luo Mengmeng grew up, he often thought of her in the dead of night. When he saw a boy approaching her little girl, he felt very uncomfortable. This made Shen Muzhi realize that his feelings for Luo Mengmeng had quietly changed...
Thirteen-year-old Luo Mengmeng was very sad about Shen Muzhi's joining the army. Without Brother Muzhi to accompany her, protect her and play with her, Luo Mengmeng was very sad. Brother Mu Zhi joined the army for five years and returned home only a handful of times. However, because Luo Mengmeng was in school and never saw each other a few times, Luo Mengmeng's longing for Brother Mu Zhi gradually turned into a certain kind of affection, which grew crazily and took root...