Carl B. Gacono, Ph.D.
et al., (1995) published a small study for The Bulletin of the American Academy of Psychiatry and the Law comparing "select behavior indices between
hospitalized insanity acquittees (N = 18) and hospitalized insanity acquittees who successfully malingered (N = 18)". The study authors called the malingerers 'severe psychopaths', which was evidenced by the fact that all of these malingerers engaged in physical or verbal violence against the staff of the facility, and that a large amount of them were convicted rapists, murderers etc.
They found that these severe psychopaths were so likely to have consensual sexual relations with female staff, that in fact, 39% had such consensual relations with female mental health staff when the researchers evaluated this. Some (the precise figure was not mentioned) even married the female staff members.