Madam operates a bar where the financially cut-off protagonist Yozo Oba finds employment. Recognizing his troubled state, she provides him refuge and later marries him, offering shelter and financial stability. Through marriage, she becomes a maternal figure attempting to guide Yozo toward stability, leading to the birth of their child.

This relative stability deteriorates as Yozo's mental health declines and drug dependency deepens. Madam's role shifts from caretaker to victim when she discovers Yozo engaged in a sexual encounter with a recent widow, a customer at their bar. This devastating discovery irreversibly fractures their relationship.

Following this betrayal, Madam's fate intertwines with Yozo's downward spiral. She ultimately dies by suicide alongside their infant child. Her death profoundly impacts Yozo, intensifying his guilt and alienation. It marks a pivotal moment in his descent, symbolizing the collapse of his last meaningful human connection and reinforcing his self-perception as fundamentally disconnected from humanity. Her background prior to meeting Yozo remains unexplored.