I have my slave bound in a chair so that his cock is exposed to my torment. I decide that I want to play with the milking machine, but I don't really want to have him cum. I just want it to stimulate him continuously without any real pleasure.. So I fiddle with the controls for a while until I'm satisfied with the intensity and stroke, then torment his cock until I'm entertained. The machine keeps him hard but it isn't enough to give him an orgasm.. pefect!