As a poison tester, Cora Quinn suffered daily torture at the hands of the Poison King, living a decade of agony refining poisons. Her life changed when her stepmother retrieved her and forced her into a substitute marriage—by chance, she turned out to be the only antidote for Grand General Robby Nash. She then began being cherished by all in the Nash Mansion, and together with her husband, she became the untouchable mistress of the household.