A woman said her boyfriend felt outshone by her vibrator - so she invented a barely-there sex toy that people with penises hardly notice

• Piri Miller patented a couples vibrator, called Petl, that has a low profile and C-shape so you forget it's there.
• Miller told Insider she came up with the design, which she now holds a patent for, after her ex complained about bulky sex toys.
• The Petl has a motor running all the way up the device, rather than just vibrating at the end.

When Piri Miller's boyfriend said using vibrators during partnered sex overshadowed his abilities as a lover, she ran with his insecurity.

Miller is now one of the only women to hold a patent for a vibrator design. The Petl is hands-free and has a low profile and flexible C-shape, characteristics Miller became obsessed with after reflecting on her now-ex's comments.

"I knew I really had something when it was done and he told me that he couldn't feel it," Miller told Insider of a Petl test run she did with her ex.

This year, Time magazine named Petl one of the best gadgets at 2020's CES, a massive annual technology trade show in Las Vegas.

Today, sex toy companies tend to recycle existing technology to create the vibrator designs you see on adult store shelves, two sexual health experts told Insider. But they said the Petl has unique feature that solve common issues - including chafing and poor fit - that's likely thanks to Miller's dedication to user feedback.

Miller recruited space suit and car prototypers to create her vision - and had to fend some mansplaining

Miller always knew a vibrator was her key to a great orgasm.

"We have a manned space station, but there's no comfortable way for me to have an orgasm reliably with a male partner," Miller, who lives in New York, told Insider.

"I have a lot of sympathy for men, but they need to loosen up a little bit," Miller said of their sex-toy insecurities.

Miller had no experience with user design - she studied psychology in college, then worked for non-profits in youth development and financial aid - but she had a vision.

She met with Brooklyn protypers known for designing space suits, and they created Petl's first iteration, a mess of silicone and cheap aluminum.

After settling on a steel spring frame design, Miller headed to Detroit to work with car prototypers, who brought her design to working condition.

They helped her develop the device's signature feature, with a motor running all the way up the curved area so it lines up with the clitoris, rather than containing a motor at the end.

But she had to fend off a few men's opinions first.

"There have definitely been some men that have very aggressively tried to mansplain vibrators and vaginas to me. That's been very interesting," said Miller.

She recalled one male prototyper who suggested moving the vibrator's motor to hover over the vagina, rather than the clitoris, as Miller wanted. Another suggested making the vibrator look like an anatomically correct vulva.

"He was like, 'Because like women love that.' And I was like, 'Are you sure? Because I really don't think [heterosexual] women love that,'" she said.

To test Petl, Miller wore it while doing dishes

Once Miller had a working model, she relied on herself and her investors for feedback.

One investor, a friend and biologist-in-training, gave Miller a 25-page feedback document which she said was "a blessing."

"When I texted her and I said, 'Hey, I got a new prototype,' I couldn't even stop her. She was at my door being like, 'I am taking this. Thank you,'" said Miller.

Investors who donated to a crowdfund at the start of Petl's journey have also provided feedback, which Miller uses to create updated prototyes. She says her main concerns are if the Petl stays in place while in use and comfortability for both male and female users.

After testing Petl with her then-boyfriend, Miller also tested the vibrator's usability for singles, wearing it while she washed dishes.

Now around six months out from an official release, Miller is diversifying her testing pool and creating multiple sizes of the Petl to fit a wider range of customers.

Sex toy experts say Petl has the potential to fill a gap in the market

According to Taylor Sparks, an erotic educator and founder of intimacy shop Organic Loven, Petl's slim design could solve uncomfortable chafing and rubbing for people with penises, a common problem she hears about when it comes to couples' sex toys.

She also said Petl's flexible C-shape is ideal, since "no two vulvas and vaginas are alike."

But perhaps Petl's most redeeming quality is Miller's interest in user feedback. Rachel Wright, a New York City sex therapist and educator who consistently tests sex toys, said her favorite sex toy brands, like Dame, use fans' compliments and critiques to create new products.

"I do tend to have a bit of skepticism about products being marketed as the next greatest design, but when companies design toys based on reviews, asks, and what their audience is looking for, it makes me more excited to try the product," Wright, who hasn't tested Petl, told Insider.