The heroine Tao Ci had a crush on her neighbor Song Jinchu who lived upstairs in her high school. Song Jinchu was one year older than the heroine and was in the same high school as the heroine. Her parents lived in M with their younger sister Song Xuanxuan. Song Jinchu was left to live alone in City A, paying living expenses to the male protagonist's bank card regularly every month.
An accidental bet connected two unrelated people...
Concept: I don't know how to write it