For the team at Dipsea, a podcast app that releases erotic sex-positive audio stories, the crucial piece in any of their shorts is the listener’s imagination.

In a world where so much of readily available pornography is visual, Dipsea is challenging its subscribers to rethink sexuality. By processing erotica through their headphones, listeners are “envisioning something based on the blueprint that we give them”, Gina Gutierrez, one of Dipsea’s founders, said.

“The truth we hold dear is that sexuality is as psychological as it is physical,” Gutierrez continued. “It’s not just about stimulation. It’s about imagination. It’s about inspiration.”

Dipsea began, like many of its stories, over late-night chats and wine. Gutierrez and her co-founder, Faye Keegan, would sit around their friends’ kitchen tables in San Francisco, talking about Keegan’s affinity for the Starz series Outlander and its many sexy scenes.

“That kind of experience is many women’s stand-in for erotic content,” Gutierrez said. “They’re not watching it to get off, they’re not watching it to get turned on, but then they eventually are because it’s really good, erotic content.”

When Gutierrez and Keegan first started exploring the concept of the app, they found a gap in the market. There were romance novels, a $1bn-a-year industry in the US, but those require time and commitment in a way that a visit to PornHub does not. There is online written erotica and even online audio erotica, but much of it is user-generated and of variable quality.

They knew that in this day and age, plenty of women do find satisfaction in the available erotic content out there, whether it be visual or the written word. But they also felt many women were seeking another form of erotica that the market just hadn’t yet developed.

“Then one night, I was listening to the Headspace podcast and thought, this is what I’m talking about,” Gutierrez said. “It’s super sensory, it makes you feel something, you feel better after you listen. It’s not just about the listening – it’s about what happens afterwards. You feel relaxed, you feel more connected to your body.”

Dipsea launched in December, part of a booming podcast industry. Globally, 287 million people listened to at least one podcast a month in 2016, a figure that is expected to grow to 1.85 billion by 2023, according to the research company Ovum. Global podcast advertising revenue had reached $490m by the end of 2017, with the market predicted to hit $1bn by the end of 2020.

With a podcast for any interest, be it dentistry or women drinking wine and talking about murder, sex has found a home in the medium as well. Bawdy Storytelling features true stories about sex, while the sex-advice columnist Dan Savage answers sex and relationship questions on Savage Lovecast. Few have gone the route of Dipsea, however, in generating regular original fictional content, produced with voice actors.

“In a way, audio is a retro medium,” Gutierrez said. “When podcasting started blowing up, a lot of people were like, what? Because video was and is the future. But I think there’s something to be said about the zone-out, couch-potato feeling when you’re in front of a screen. Your mind is doing no work. You’re just consuming, consuming. Audio is a break from that in some ways. Audio makes your brain work more.”

Dipsea now has more than 120 stories in its library, each running between seven and 15 minutes long. The narratives range from former lovers meeting in a chance encounter on the train, to two strangers hitting it off at the same airport gate, or a close friend joining a couple in a threesome one late night.

The buildup to the sex oftentimes plays an even more substantial role than the actual acts itself. The characters feel like they have depth, emotion and a full narrative arc, but they lack the heavy-handed physical attributes so common in romance novels.

It’s an omission by design, according to Olivia Taylor, Dipsea’s content editor. By purposely leaving the physical qualities of the characters vague, the writers allow the listeners to fill in the blanks. “‘A lanky frame’ or ‘round arms’ are evocative while still leaving a lot of room for the listener to imagine and visualize characters in all the ways they want,” she said.

“We prefer to focus on the ways in which characters connect beyond physical attraction,” Taylor continued. “Personal dynamics are relatable, and frankly, more universal than physical attributes. We take the perspective that it’s probably less about the color of someone’s eyes and more about the way they make you feel when they look at you.”

“It’s almost like a visual soap opera,” said Nenna Joiner, sexologist and owner of Feelmore, Oakland, California’s only black-owned sex shop, of the Dipsea stories. “It’s almost like lying next to them and watching them in bed, and they don’t see you. You get to see them and experience it, versus in porn, you don’t want to get too close. You want them at arm’s length.

“I think with Dipsea, it gives you the opportunity to plant flowers, enjoy them, water them, even give them to someone,” she added.

The team has one writer on staff and works with freelancers to make sure the app can push out three new stories a week. “We are constantly, constantly balancing for breadth,” said Gutierrez, adding that they were always looking for stories from different perspectives.

At a recent editorial meeting, Taylor and the staff writer, Emily Acker, pitched a three-story serial centered on a female bisexual Casanova type, structuring the character around the strong women in the TV shows Killing Eve and Gentleman Jack. “I think there’s a way to be a player and be straightforward with people,” Taylor said. “I want to feel like this character feels that they’re being straightforward with people about what they want. I don’t want them having a bunch of sex because they’re emotionally damaged. They’re just not interested in a long-term thing right now.”

The writing and storytelling is only part of the equation, Taylor said. Much of a story’s success rides on a voice actor’s performance – and their ability to “conjure ideas and expectations in a listener’s mind”, she said.

Figuring out ways to make the physical sounds of sex sexy is a constant challenge for the team, Gutierrez said. “What is real and sensual and exciting in real life might not translate in audio,” she said. “Lube being squeezed out of a bottle: we all know what that sounds like. It’s a very normal noise for people, but you don’t want to hear that in your ears. But the crinkle of a condom wrapper is a very good way to indicate that safe sex is happening without having to say, ‘I’m grabbing a condom from my bag.’ But then, on the other hand, sloppy kisses, not great. You don’t have to hear all of it.”

Though they started the venture because they felt women were underserved, 15% to 20% of their listeners are men, Gutierrez said – a testament to the company’s mission to create inclusive and empowering content. In focus groups, the company has heard from couples listening to the podcasts together and men who are listening to learn, Gutierrez said.

“This is something that can slot into people’s lives pretty easily because it’s so short; it opens up a new possibility of how you can use it,” she said. “When you’re watching porn, the experience is basically end to end, the length of the video. With Dipsea, you’re engaging for those minutes, but it’s what happens next that I think is really exciting.”

It could be something as simple as being more relaxed and falling asleep, Gutierrez said, or feeling more flirty and confident and able to go out and meet somebody. Women are quick to feel guilty for coming home feeling too tired and stressed for sex, but the app can act as a pick-me-up, she said.

“We make a lot of sense to someone who is looking at their sexuality really curiously, and exploring what it means to be a sexual being,” Gutierrez said.

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