Tesla reassures Jonathan that he will take care of him. He places his hand over Jonathan’s chest and gently orders him to relax.

“Tell me when you can feel the power,” Tesla says.

Jonathan clenches his jaws around the rubber gag tied across his mouth. He grunts. A leather blind-fold covers his eyes. He moves his hips as if he is trying to fuck someone in the air – but Jonathan can’t move. Tesla has strapped all 5 feet 10 inches of Jonathan down – at the arms, chest, legs and ankles – against the leather-lined table in a dimly lit living room turned dungeon for this evening’s “scene.”

It is a morphine-like high for Jonathan when the endorphins secrete. He feels pain from the electrical power, and then pleasure from the electricity that surges through a butt plug in his anus and out of two “cock bands” placed snugly around his testicles and at head of his penis.

“It feels like you’re being fucked or someone is kneading your penis. It makes you feel tingly, pulse and quiver,” says Jonathan about his experience with electric sex, while driving home. “Since it is genitally focused, cocks and balls, vagina or ass, it’s not something for the public.”

The sound of a band playing on Folsom Street echoes loudly into an emptied 10th Street, which is blocked off for the Folsom Street Fair. Uncle Abdul, a large, towering man with a snow-white beard, wears a baby-blue collared shirt and denim jeans. He looks for a spot on the pavement to place his bag filled with electrical goodies, then begins to talk about his experience with electric sex in San Francisco’s BDSM (Bondage, Domination, Sadism and Masochism) community in the 80’s. Abdul, author of “Juice – Electricity for Pleasure & Pain,” estimates that today, about a quarter million people practice sex with electricity worldwide.

Orgasm can be achieved with a variety of devices that are now available for those who go electric. Two of the most widely used electric-sex devices, initially intended for medical use, are the Violet Wand, which produces static when placed near the skin and a TENS unit (Transcutaneous Electrical Nerve Stimulator), which stimulates nerves by sending electrical pulses to an attachment, such as an electrode pad.

After 15 years, electro-sex devices now include commercial TENS and TENS-like units, specifically designed for electrical play with delivery attachments such as anal, vaginal and urethral inserts, probes, catheters, and clips – more accessories to put in a bag… next to the whip.

Many in the BDSM community point to the 50’s Relaxacisor as the first electrical device used for sexual stimulation in modern times. The device was originally created to stimulate muscles. Adventurous types found other body parts on which to place the pads.

“There are a small number of cases that, if you really don’t do it right, the first thing you know that something has gone wrong is that you or your partner is dead,” Abdul says. “It basically affects the heart and it can stop the heart or produce a burn that might take some time to heal.”

Abdul is a licensed electrician by day. He says there are additional safety precautions: no electricity near the eyes, ears or mouth since there is a probability of blindness and loss of hearing.

And there are ways make it go right. If the accessory unit is unipolar, there must be another unit for electricity to go out. “Electricity has to go into a circuit and out of a circuit in order for it to work, a point of entry and a point where a current comes out. People are coming up with a lot of different combinations all the time.”

And that means electricity can go into wrist and out an elbow or into an anus and out a vagina or into a nipple and out a penis. “Some circuits work better than others,” adds Abdul.

Ancient Egyptians used electric fish to alleviate a migraine. Today, a $4 electrode and a $400 Violet Wand or TENS unit can produce an electric-pleasure fuck to make Jonathan’s toes curl.

“As more and more people are finding out that it is OK to express their sexuality,” Abdul adds, “the attraction of modern technology is something that encourages people to: ‘Gee, I think I’ll try this.’”