Disturbed characters most often target folks possessing two qualities they don’t posses: conscientiousness and excessive agreeableness (i.e. deference). So, it’s a solid conscience that makes you most vulnerable to narcissistic manipulation. Manipulators use guilt and shame as their prime weapons. But you have to have the capacity for shame and guilt for the tactics to work. Disturbed characters lack that capacity. Conscientious folks have it in spades.