A young girl, Su Yi, is terminally ill and loses her memory in an accident. Su Yi hopes to see her lost sister before passing away. On the train leaving, I met a young girl, Xiao Rang. During that period, Su Yi found that he had a strange dependence and liking for Xiao Rang and Sang He. Su Yi met "Little Superboy" who played in the band in the underground passage. Superboy told her that he once loved a girl who was very similar to Su Yi. Superboy got into a fight with someone and was sent to the hospital where Xiaorang was for rescue. Su Yi went to visit Little Superman, but unexpectedly heard the conversation between Kang Dong and Xiao Rang at Xiao Rang's door. It turns out that Xiao Rang is the sister Su Yi that she has been looking for for a long time. The boy Su Yi likes may be Superboy.