I'm fairly certain there needs to be direct genital stimulation for an orgasm to be reached, or at least that's my personal experience. I certainly get incredibly aroused through BDSM acts, and would say that they excite me and arouse me more than vanilla sex acts. I'm not about to get off by being blindfolded or spanked...but it would certainly help
The answer to this question is. No you do not have to have genital stimuli, trust me. They are just usually the easiest to stimulate. The better the stimulator, real or fake, human or prop, the easier to stimulate. No matter where the application.
--
Those who can make you believe absurdities
can make you commit atrocities.