Scientists build sexual contact network from reviews of soaplands nationwide

Here at Tokyo Kinky, we pride ourselves on how we strive to keep up with the latest research and fieldwork. It’s a tough job, but someone’s gotta do it.

And so when we see an academic article titled “Exploring sexual contact networks by analyzing a nationwide commercial-sex review website,” it’s a no-brainer whether or not we read. Even if it’s written by ecologists.

Though framed in academese, the article is essentially looking at reviews for soaplands on a website that covers 66% of establishments in Japan (784 soaplands) and has more than 2 million members and information on 38,964 sex workers. That’s quite a lot of data. There were 1,185 soaplands registered with the police in 2021. (Soaplands, where clients receive an intimate bathing experience, are regulated and licensed according to prefectural ordinances and monitored by local police.) However, just 3% of the website members wrote reviews on the site, so reviews constitute just a fraction of the real scale of sexual contact.

The review website is not named in the paper, from what we can tell, but we suspect it’s Soap BBS.

The article was actually first published online on an open-access academic website last November but has been picked up by the Japanese media this month.

The authors, who falsely claim that soaplands are “the only type of sex industry in Japan where sexual intercourse is publicly permitted” (full service is not officially permitted and soaplands are just one of several sex services that are only available), say that their paper “clarified the network structure of commercial sex, characterized by small-world, scale-free, and disassortative mating properties.” We have no idea what this means but perhaps reading beyond the abstract will enlighten us.

So we did. And the conclusions?

“We determined that active female commercial sex workers (FCSWs) constitute an important pathway of infection propagation in commercial sex networks, but male clients (MCs) also play an essential role as weak ties.”

So going to soapland forms a sexual contact and can create a pathway for infection if one of the parties involved has a sexually transmitted infection. We knew that already but OK.

But wait, they thoughtfully clarify!

“We emphasize that our study should not give the impression that soaplands (and many other types of sex trade industry in Japan) are possible hotspots of STIs. In fact, our analysis does not provide any evidence or relations between STIs and sex industry; furthermore, a previous study reported that the incidence of STIs among FCSWs in soaplands was relatively low.”

So that’s a relief.

The paper is ultimately trying to form a sexual contact network that is large and nationwide (in fact, they claim the review website allows them to obtain the largest such network to date). This shows us pathways for potential infection — but it’s just potential.

By formulating the sexual contact that occurred between the review writers (MCs) and “review receivers” (FCSWs), the authors built visualizations of the sexual contact networks that these reviews constituted. “This study provides important baseline material for the structural characteristics of large-scale commercial sex networks.”

Reading on, though much of the language in the “results” and “discussion” sections was beyond our mediocre minds, the study notes the cross-prefectural nature of soapland visits (since some prefectures ban them or because clients want to visit a particular establishment).

We could, at least, parse the implications of this part: “FCSWs constitute an important pathway of infection propagation in commercial sex networks, and MCs play an essential role as weak ties. Therefore, our results reveal the potential STI diffusion effects of active MCs who use multiple brothels in different areas.”

Perhaps the long and the short of this is that visiting a soapland and writing a review of your trip could benefit scientific research, so there’s now no reason not to go (as long as you use protection).