Sometimes killing by male-female couples represents an escalation of an adventure that starts with entirely, or at least relatively, harmless activities, as in looking at fringe pornography, sharing fantasies or accounts of earlier experiences, S&M or swinging. In some cases, this could be seen as grooming by the male. The existence of killer couples raises the issue of whether the female derives sexual pleasure from killing or the pleasure comes solely from pleasing the male . In each of the couples described here, the male would appear to be the dominant partner. For Ian Brady and Myra Hindley, it is unclear what set them on his tragic course. For Brady, it was possibly resentment against illegitimacy and social standing. Fred and Rosemary West both came from abusive backgrounds. The case of Paul Bernardo and Karla Homolka raised the issue of whether Homolka showed evidence of Stockholm Syndrome.