"I'll put it on for you. When I'm not around you and you're unhappy or bullied, think of it as me. I'll protect you and you'll be very happy." In the picture, a handsome little boy puts on a necklace for a little girl. The little girl always remembered that the boy said he would protect her, and she always believed that one day they would meet again. Many years later, when Xia Yuqin meets Luo Su, will Xia Yuqin find out that Luo Su is the little boy who said he wanted to protect her in her childhood, and Luo Su has always known that Xia Yuqin is the little girl in her childhood. Luo Su did not tell Xia Yuqin, but stayed by her side to guard her silently.