If you have been on Steam, the world’s largest PC gaming platform, you might have noticed an anomaly on the chart of the top 20 most popular apps: Wallpaper Engine. The software is pretty cool—it lets you download animated and interactive wallpapers for your machine’s monitor—but it’s hard to explain why an obscure wallpaper app consistently ranks alongside global blockbuster franchises like Counter-Strike or Dota.
The epiphany will come when you begin to read Wallpaper Engine’s many reviews. More than 200,000 of them are written in Chinese, stretching from 2016 to 2022. And these reviews almost all talk about one thing: porn. Or more specifically, about using the software as a cloud drive and a video player for exchanging adult-only content.
Online porn is banned in China, so people there have to get creative to access it. Steam is one of the only popular global platforms still available in the country, and its community features, international high-speed servers, and increasingly hands-off approach when it comes to sexual content have made it an inevitable choice. Chinese users now make up at least 40% of Wallpaper Engine’s global user base, MIT Technology Review estimates.
Last year, users in China suddenly needed to use VPN services to access certain Steam services. As the reviews show, now they are afraid they may soon lose this rare community, either because of platform content moderation or the possibility that China might block Steam altogether.
An open secret
Wallpaper Engine, developed by a duo based in Germany and first released on Steam in October 2016, allows users to switch out their static wallpapers for something more dynamic. The majority of user-submitted wallpapers in the software’s Workshop are innocuous: anime characters, cyberpunk cities, landscape drawings, and movie posters. But it’s also not hard to find NSFW content in between: about 7.5% of the over 1.6 million contributions are labeled “mature.” These are often nude anime characters in suggestive poses and sexual positions, and occasionally pornographic photos and videos of real people.
Despite Wallpaper Engine’s success as probably the most “played” non-game software on Steam, its erotic side has rarely been reported in English, except for a short article in the gaming media Kotaku and sporadic discussions on social media. Yet within Chinese online communities, it has been an open secret among gamers and gaming publications since it was released.
“It was at least two or three years ago when this went viral,” says Zhou, a Chinese gamer in Beijing who asked to use only his last name due to privacy concerns. “I was confused why it was always [on the top 10 played games ranking]. Did people like to change their wallpapers so often?”
Cui Jianyi, a Chinese writer and journalist, wrote about the phenomenon in 2020 after he saw someone mention it on social media. Having been a gamer and a Steam user, he downloaded Wallpaper Engine and tested it. There he found porn, hentai anime, Donald Trump memes, and even pirated copies of Hollywood movies, like Joker. His article in the Chinese media helped bring the software’s hidden uses to the attention of those who were not yet in on the secret.
It’s impossible to know exactly how many of Wallpaper Engine’s users are from China, but evidence suggests that at least 40% of them are Chinese, almost twice Steam’s Chinese user percentage.
Among the nearly half a million Steam reviews of Wallpaper Engine, 40% were written by someone whose default language was simplified Chinese, compared with English at 28%. More recent reviews follow the same trend: during the first seven days of July, the software received 2,907 Steam reviews, and MIT Technology Review has found that 40% of those were written either in simplified Chinese or by someone with a simplified Chinese username. (Language is a common proxy for Steam users’ geographical distribution, which is hard to collect on Steam.)
Meanwhile, only 24.75% of total Steam users set their default language as simplified Chinese, according to Steam’s latest sampling survey, from June 2022. A different stat by Steam suggests that 21% of overall traffic came from China in the seven days before the publication of this story. Compare this with 40%, and it’s clear that Chinese users are overrepresented in Wallpaper Engine’s user base.
They are also some of the most devoted users of Wallpaper Engine. The top 70 most upvoted reviews of all time on Steam for this software are all written in simplified Chinese. “What’s the sickest [coolest] is that someone straight up uploaded porn to the [Steam] Workshop,” reads one March 2019 review in Chinese, upvoted by 456 others. The user proceeded to log over 5,000 hours in Wallpaper Engine.
The developers, who keep a relatively low profile online, likely know how their software is being used thousands of miles away. When Kristjan Skutta, one of the main developers, was invited to China in 2019 to attend an event, Chinese media asked what he thought about the fact that the app was being used to watch certain types of videos. “What’s wrong with that? Wallpaper Engine is only a framework. No matter what you upload to it—even those crazy videos—I don’t think there’s any problem,” Chinese publication Xiaoheihe quoted Skutta as saying, after he laughed at the question. Neither the developers nor Steam responded to MIT Technology Review’s requests for comment.
The lack of access to porn in China
Compared with countries like the United States, where pornography websites are legal and easy to find, China maintains a much harder stance. Most adult-only websites are banned, and such content is also routinely removed from social media, cloud drives, and all other online services.
In addition, uploading or reposting porn can be considered a crime. In 2016, the founder of the Chinese video player QVOD was sentenced to three and a half years in prison because the company allowed the software to become a popular hub of porn video torrents. And in several cases in the past two years, Chinese users have landed in prison for six to eight months for merely reposting porn on Twitter.
“Consuming erotic content is a basic need,” says Cui, who recalls that websites like Pornhub were gradually censored in China as he was growing up. “If there are no legitimate porn websites, then people will consume it wherever they can find it.” Not everyone in China can afford to spend a lot on VPN services, so they have to find platforms that aren’t completely blocked, like Steam.
In fact, Steam is in a unique situation right now. “It has become one of the only platforms in China where it’s sort of operating in the gray area,” says Daniel Ahmad, a UK-based senior gaming analyst at Niko Partners. Under China’s strict regulations on game publishing, Steam should have been banned a long time ago. “But for some reason, it still exists,” Ahmad says.
With almost all international social media platforms now unavailable in China, Steam has become one of the only places where some Chinese people, at least gamers, can communicate directly with overseas communities.
Many Steam users are worried that this precious paradise could be lost any day. Several confirmed to MIT Technology Review that since 2021, VPN services are required to access some services, like browsing and purchasing games, while other functions, like downloading and playing games, remain unrestricted.
It’s unclear why Steam’s service is only partially restricted, as most foreign websites are either completely blocked or not blocked at all in China. But Ahmad says the recent changes have driven Niko Partners to upgrade the risk assessment of a Steam ban in China to “high.”
There’s also the fear among Chinese users that one day Steam or the developers themselves will turn against such uses of the software. Chinese users of Wallpaper Engine note that content gets taken down regularly, presumably by moderators. In the online troubleshooting Q&A for the software, developers wrote, “We and the Steam administrators/moderators remove wallpapers breaking the rules on a daily basis. Please report Workshop submissions that break the guidelines to help us find them.” On the flip side, a big chunk of the Chinese reviews are asking fellow users not to report NSFW content or even talk about this software elsewhere as they want to keep it under the radar.
Chinese users of Wallpaper Engine just want to enjoy the freedom they have now, knowing this party will end someday soon. In one Steam review upvoted by over 1,800 users, a creator shared his experience of uploading erotic content and constantly dealing with content removal and account suspension. In the end, the user wrote, “perhaps one day, [Wallpaper Engine] will really turn into a piece of wallpaper software!”
When that day comes, Chinese users will need to find yet another ingenious way of sharing porn.