Xiao Fei is a student of Shi Yi Jie, a divorced assistant anthropology professor with a daughter, who is between seven and eight, who takes over a colleagues life and death class when she goes into early labor. Through a series of events, the three become family as Xiao Fei starts as You You's nanny, and eventually becomes family. It's a beautiful story and both are clearly broken by life, but with vastly different outlooks and a common affection for You You. When they realize their love, it is beautiful, and Xiao Fei's bestie awesome. I rewatch this regularly because I love the characters so.