The Underworld Agent Became a Rejected Heiress

An underworld spirit travels across worlds to avenge wronged souls. Taking over the body of a noble's trueborn daughter swapped at birth and cast aside for an imposter, she refuses to suffer in silence. Accompanied by her magical partner—trapped in the body of a duck—she drags her coldhearted father to court, forcing him to acknowledge her bloodline. Returning to the manor in triumph, she begins her payback. But how will her corrupt family face the storm of vengeance she unleashes?