Gu Zhiyi always treated her younger brother Shen Muyan as a real brother until the day he came of age. The young man suddenly pressed her shoulder and said in a serious and aggrieved tone: "Sister, I don't want to be your brother, I want to be someone who can stand by your side." Shen Muyan's clinginess was a habit engraved in his bones: when she was on a business trip, he would travel thousands of miles to send him warmth; when she was wronged, he would immediately stand up for her; he could remember her casual preferences better than anyone else. From the childish "Sister can only be nice to me" to the mature "I will always protect my sister", this clingy brother quietly melted Gu Zhiyi's defenses with his gentleness day after day. When sweet dependence turns into two-way love, they understand that the best love is that she can't live without him just as he clings to her.