The lab is staffed by a small group of artists who meticulously craft individual body parts en masse. There's a man painting erect penises, another carving the contours of a cheekbone, and in the far right corner sits an empty workstation for the lab's dedicated eye technician. Just across from a makeshift collage of immediately recognizable celebrity eyes are rows of upright canisters capped with muffin-top-shaped silicone mounds and bright red glossy lips.

I'm immediately reminded of my night with the Autoblow 2+, and for good reason: McMullen tells me he's manufacturing high-end inserts for that lackluster coitus can. Throughout my four-hour tour of the space, I can't shake the feeling of familiarity. Even when I'm introduced to Harmony, a RealDoll with an AI-equipped, robotic modular head, I get a sense of deja vu.

While male sex toys have reached their technological zenith in Harmony, the basic driving design principle is centuries old. Left to their own devices, men have routinely reached for anthropomorphic masturbation aids. Meanwhile, women have their choice of Rabbits, Magic Wands and all forms of amorphous vibrators. When RealDoll releases Harmony's robotic modular head later this year, it will be the closest we've come to the sex robots of Ex Machina and West World.

And, unsurprisingly, it's a girl!

"So, the initial rollout will be the female head, and the reasoning for that is, you know, just based on our own product line and what we sell," McMullen says. "You know, percentage-wise, we sell obviously a lot more female dolls than male."

For McMullen, it's simple economics, but it's less obvious why sex dolls, and presumably sex robots, are more popular with men than women. With that in mind, I called Carol Queen, resident sexologist at the woman-run Bay Area sex shop Good Vibrations, to talk about the difference between men's and women's sex toys and, most important, why my first sex robot won't have a penis. According to Queen, the explanation is a lesson in three parts: history, anatomy and psychology.

In the back of Good Vibrations' flagship store in San Francisco's "Tendernob" district (somewhere between the Tenderloin and Nob Hill), Queen has curated perhaps the most comprehensive collection of antique vibrators. For a full history of the vibrator, she'll tell you there's no better resource than Rachel P. Maines' The Technology of Orgasm, but if you want to see that history for yourself, this is the place to be.

Queen walks me through the history of the vibrator, which has its roots in ancient Greece, as, it seems, so many of our sexual preoccupations do. The physician Claudius Galen successfully convinced the medical establishment that women's uteruses were detaching and wandering around inside their bodies causing all sorts of problems.

According to The Technology of Orgasm, that "condition," commonly known as hysteria, aka "womb disease," consisted of a vague set of symptoms found primarily in women, cured through hysterical paroxysm, aka an orgasm. For centuries, doctors gave their female patients handjobs in order to treat a fake disease, but by the mid 1800s they'd grown tired of the finger labor, and the vibrator was born. The first known vibrator, the Manipulator, was a far cry from the discreet devices we have today.



"The first patented vibrator in the United States looked like a massage table with a hole in it, and a Magic-Wand-head-shaped orb coming out that the lady would ruck her bustle up and cuddle right up to," Queen says. "The doctor would hit the steam and, like a steam-heat radiator, the steam would flow and the ball would vibrate and she'd come back next week a happy camper and want to do it again."

Queen shows me a series of early hand-cranked vibrators that look like egg beaters and a rare, compressed-air device that immediately makes me think of Whip-Its for your clit, but it wasn't until the introduction of electricity that vibrations became mainstream household appliances. The first battery-operated vibrator hit the market in the late 1800s and over the next century, the devices would go through a number of iterations. There were the early consumer models of the early 1900s, the design-driven deco stunners of the '30s and '40s and the experimental personal massagers of the '50s and '60s.

By the time the mother of them all, the Hitachi Magic Wand, hit the market in 1968, vibrators had already gone mainstream, and with the rise of the sexual revolution, we finally started talking about why they'd become so popular: MASTURBATION. While vibrators have taken countless forms, male sex toys never advanced much past their 17th-century origins.

"There's evidence that seafaring fellows used to take companions with them of the inanimate variety, called dame de voyage, or homme de voyage if they were gay," Queen says. "And they were created to be inanimate sex companions, which evidently was better than not having any sex companion at all, which is probably something that we could say about the people who purchase the dolls today."

Over time they would evolve from the makeshift ragdolls to the hyper-lifelike silicone RealDolls, with leather, rubber and latex versions in between, but they all attempted to mimic the human form.

While male and female sex toys followed two distinct paths, in both cases form followed function. Both male and female sex toys were historically designed to give the user an orgasm, but only one of us was optimized to orgasm from penetrative sex. As Queen points out, the clitoris and the head of the penis are essentially the same body part. Only the clit doesn't get the same attention as the dick head during the old in-and-out.



"What optimizes female orgasm is clitoral stimulation, and there isn't adequate clitoral stimulation during intercourse, and it's just that simple," Queen says. "The clitoris and the penis are basically the same thing. If you ask the guy to get off without touching his penis, except sort of randomly a little bit, like he could get as turned on as he wants, but no grabbing, no thrusting into his hand, no back and forth with lube, no rubbing on the sheets even, no any of the things that he usually does. Some men are sexual athletes and could find a way to do it, but most cannot."



When you consider the statistics, the fact that there's not a whole lot of demand for toys that look like dicks isn't all that surprising. In her seminal work on the subject, The Case of Female Orgasm: Bias in the Science of Evolution, Elisabeth A. Lloyd found that only 25 percent of women reported routinely orgasming from vaginal sex. Studies show that women are far more likely, on the whole, to orgasm from masturbation (and you don't need a penis for that).



If you want to really understand why the world's first sex robots are basically AI-equipped blow-up dolls, though, Queen says you have to get inside a man's head -- the one on his shoulders. She points to the widely held belief that men are more visual creatures. That ocular preoccupation has been used to explain why we value looks over brains and watch more porn than our female counterparts. Queen believes there's also a level of pride that limits a man's imagination.



"When we start to talk to men versus women about the question of using sex toys, there really are a lot of men who are hesitant to use toys because it seems to them second-best, in a particular way," she says. "There's a complicated relationship that women might have about this kind of stuff, too, you know. Sometimes people do masturbate because they don't have a partner, because they're lonely and sexually frustrated and they want to take care of themselves, but sometimes people masturbate as a liberatory act, to take themselves out of the box of expectation, and there is a lot more discourse about that for women. A lot more."



Queen argues that women have had to explore their sexuality in more depth as a result of historical sexual repression (hello, Galen). The necessarily politicized discourse that encourages women to explore their sexuality demystifies and even encourages the use of sexual aids that don't resemble or act like a human at all. There's also the whole "dicks are easy" thing.



"There's this kind of encouragement that we give women -- not that we don't give it to men, but it was developed out of this need to talk to women around remedial issues like, 'I don't know for sure if I'm having an orgasm,'" she says. "And fellas know, at least if they're ejaculating. Whether that's the same as an orgasm is a whole other discussion, but at the very least most men find their penises at a relatively early age."



Whether it's simple economics, a history steeped in sexual inequality or our shared anatomy, the most sophisticated sex toys targeted at men today, the earliest manifestations of the sex robot, have all been designed to mimic women. That singular focus not only perpetuates issues of gender inequality, but it also limits the kinds of relationships we can have with our machines. In a world where everything is rife for disruption, we seem perfectly happy with robots that maintain the status quo. Queen believes that the mainstreaming of sex robots is inevitable. She imagines a day when we'll be able to plug our dildos into our sensory systems and "feel the dildo's feelings."



But before we can expect sex machines that do more than serve a stereotypical straight male audience, we'll have to think outside of the box.