Objective: The current study investigated actor and partner effects and the effects of (dis)similarity in the dark triad traits on self-reported relationship satisfaction of both members of romantic couples. We examined these effects on actual similarity, similarity of perception, and men's and women's perceived similarity.
Methods: On the sample of 205 heterosexual romantic couples, we administered questionnaires for measuring self-reported and partner-reported psychopathy, Machiavellianism, and narcissism, as well as self-reported relationship satisfaction.