Later this month, people in Berlin will be able to book an hour with an AI sex doll as the world’s first cyber brothel rolls out the service following a test phase.

Customers will be able to interact verbally with the AI dolls as well as physically.

“Many people feel more comfortable sharing private matters with a machine because it doesn’t judge,” says Philipp Fussenegger, founder and owner of Cybrothel.

“Previously, there was significant interest in a doll with a voice actress, where users could only hear the voice and interact with the doll. Now, there is an even greater demand for interacting with artificial intelligence.”

It’s just one of many ways that generative AI is being used by the adult entertainment business.

Analysis by SplitMetrics revealed that AI companion apps reached 225 million downloads in the Google Play Store.

“I would expect more app developers to take note of this trend and look at ways this category can be further innovative and monetised,” said SplitMetrics general manager Thomas Kriebernegg.

AI companions can be lucrative, says Misha Rykov, privacy researcher with Mozilla’s Privacy Not Included guide.

“Given that most of the chatbots are charging fees, and the core technology has been developed elsewhere [such as Open AI], it looks like a high-margin business. Also, these apps collect personal data and often share it with third parties like advertisers – a tried and true business model.”

But the merger of AI and the adult entertainment business has set off alarm bells.

One problem lies in the bias inherent in generative AI, which produces new content based on the data on which it has been trained.

There is a risk that retrograde gender stereotypes about sex and pleasure get encoded into sex chatbots, says Dr Kerry McInerney, senior research fellow at the Leverhulme Centre for the Future of Intelligence, at the University of Cambridge.

“It’s crucial that we understand what kinds of data sets are used to train sex chatbots, otherwise we risk replicating ideas about sex that demean female pleasure and ignore sex that exists outside of heterosexual intercourse.”

There is also the risk of addiction says Mr Rykov, who says that AI chatbots target lonely people, notably men.

“Most of the AI chatbots we reviewed have high addictive potential and several potential harms, especially to users with mental health challenges.”

Mozilla has added content warnings to several AI chatbots “as we found themes of abuse, violence, and underage relationships,” says Mr Rykov.

He also raised the issue of privacy. Partnership chatbots are designed to collect “an unprecedented amount of personal data”.

Mr Rykov adds that that 90% of apps reviewed by Mozilla “may share or sell personal data”, while more than half of the apps won’t let users delete personal data.

Others warn about the possible danger such AI could have on real-world relationships.

Tamara Hoyton, senior practice consultant at the counselling service Relate, points out: “Some difficulties may come about if real encounters are profoundly disappointing because they don’t match up to the strictly defined requirements that users experience in AI porn.”

Ms Hoyton adds that, in some cases, AI porn could take users into dangerous areas.

“There is nothing wrong with a bit of fantasy, and many people get aroused by thoughts that they have absolutely no intention of acting on; AI porn might be seen like this.

“If it’s crossed over into an assumption of consent for example, a sense of entitlement, or that everyone will be what turns you on, based on the user’s experience of the compliance of the AI object, then it’s an issue.”

Companies using AI within the adult entertainment industry acknowledge that there is a need for caution, but maintain that AI has an important role to play.

Philipp Hamburger, head of AI at Lovehoney, says the company is aiming “to enhance the sexual experience of its customers, rather than replace it, which is an important line to draw”.

Others believe AI will have a positive effect on the sector. Ruben Cruz is the co-founder of Barcelona-based The Clueless Agency, which created one of the first AI influencers, Aitana Lopez.

He points out that the sex industry will always exist, and AI can help mitigate ethical concerns by ensuring that the content is not created using real people.

“This shift aims to ensure that no person, male or female, has to be explicitly sexualized in the future.”