After marrying into a family as a second wife, Youko finds herself trapped between her sadistic, violent husband and her emotionally distant autistic son. Tormented by her husband's escalating sexual abuse and the son who won't open up to her, she grows increasingly desperate. Seeking solace she cannot find at home, Youko begins seducing men such as insurance salesmen and laborers. But her husband's descent into madness knows no limits—he forces an illicit relationship between mother and son, driving the family toward inevitable ruin.