Following the events of her night aboard the ferry, Emanon—the enigmatic girl with a three-billion-year-old memory—continues on her journey, wandering aimlessly through life with no clear destination in mind. Since the beginning of time, she has followed the same cycle: she departs from home and travels the world as a teenager while pondering her mysterious existence, eventually meeting a man and giving birth to a girl who will inherit her memories and very being.

Sasurai Emanon, told from the perspective of Emanon herself, chronicles the events between 1967 and 1980, showing how her life had come full circle from her evening aboard the ferry to her reunion with the man at the train station.