Mo Ai grew up under the protection of her brother and became a lovely girl. Her brother's sudden departure made Xiao Ai nearly collapse, and the girl who suddenly appeared made her confused. She vowed to find out the reason for her brother's death. She changed from an innocent and good student to a sophisticated bad girl. The secret she discovered by chance left her at a loss as to how she should believe it, how she should choose, and how she should forget it.