the pervert knows what he desires. The pervert's relation to the other's desire is, or must be, a relation of knowledge, not of question, not of lack of knowledge. The masochist must be able to control the situation, he must be able to instruct the scenery either explicitly by detailed prescriptions of clothing, lines etc. or by manipulating the other to humiliate him or her. The masochist's climax is reached when he can prompt the other to think that it is her desire to kick, beat up and humiliate him; when he can make her think that she is not a puppet on a string, but a true sovereign, and act accordingly. This is the reason why sadists and masochists cannot form an ideal couple, as the agent of both parts is knowledge, the key word is control, the other must never be the Other, never be the occasion of anxious doubt.
-I think lacan was on to something.(Edited 37 seconds later.)