S/M, Sado-masochism is an activity in which one partner consensually relinquishes power to another, in one of four main areas : sensations, emotions, roleplaying or helplessness. S/m allows us to experience things that can be the most frightening and least acceptable in the real world into acts of trust, intimacy and learning.
Thru S/m people can delve into more primitives urges, it gives us permission to act in ways that may be socially unacceptable or mentally intolerable i.e. to be dependent and clingy, passive and boundaryless, cruel or manipulative. To bring these characteristics out in a 'vanilla' relationship often leads to problems between the partners. Honesty is of paramount importance. One must be honest in assessing their own needs, to be able to determine if the chosen partner is capable of fulfilling those desires.
Thru the machinations of S/M we play with power - turning it into a highly erotic experience instead of a constant struggle. Power play between couples of differing races adds an extra element to the relationship. Communication is very important. Words and actions should be discussed open and honestly to avoid slurs and slights that would spoil the time spent together. A concensus must be made as to what is and is not acceptable to both parties.
By careful discussion of the problems that plaque us as a society, working thru them honestly, the relationship can progress and enjoyment can be had by all involved.