The story of Sada Abe begins with her birth in 1905 to a poor family and her violent rape at 14. A medical student finds her, gives her medical attention, and consols her with donuts. It is only later that she discovers he was a leper who can never leave an island. She never forgets him and keeps a surgical knife as a remembrance. Soon, she is forced into prostitution until she becomes the mistress of a member of the Nagoya City Council who installs her at a lodging house that doubles as a restaurant. Sada is soon attracted to the married owner of the restaurant, Tatsuzo, and they begin an affair which is subsequently discovered by his wife. Driven from their home, they hole up in an inn where they constantly make love until Sada accidentally kills Tatsuzo during a sex game. In order to keep a part of him forever, she cuts of his penis using the leper's knife, is soon arrested, but serves a very light sentence.