What is a friend? This is a question that is easy to answer but difficult to answer. Maybe some people think that friends are just casual friends, maybe some people think that friends are just casual acquaintances, and maybe some people think that friends are just casual acquaintances at wine and dinner parties. Everyone's interpretation and understanding will be different, and the two protagonists Lin Fei and Lan Xin will show you the "friends" they know after experiencing school, career, and love, giving you a new understanding of friendship.