WTF?! The seventh most-played game on Steam right now isn't what you would expect: a wallpaper app called Wallpaper Engine. It's gained almost half a million Overwhelmingly Positive reviews, more than Elden Ring. But the app is being used for more than choosing wallpapers; it allows China-based users to view and distribute porn.

Steam's most-played games chart shows the usual names: Counter-Strike: Global Offensive is still number one; GTA V continues to hang around; Apex Legend, Rust, Dota 2, and so on. But in seventh place sits Wallpaper Engine, which boasts almost 100,000 peak players and 45.2 million hours 'played.'

That's a lot of hours for a wallpaper app. But its popularity comes not only from creating, browsing, and sharing Windows desktop wallpapers but also because it's a way to evade China's ban on pornography, hence why over 200,000 of those positive reviews are written in Chinese.

MIT Technology Review writes that while the majority of user-submitted wallpapers in the app are safe for work, about 7.5% of the over 1.6 million contributions are labeled "mature," containing videos of anime characters having sex and occasionally pornographic photos and videos of real people.

Fan-made hentai videos remain popular on certain sites and subreddits; the genre made headlines last year when someone Zoom bombed an Italian senate meeting and streamed Final Fantasy VII porn. Like all pornography, it's banned in China, leading to many female characters from Overwatch, Genshin Impact, and Final Fantasy appearing on the app in images unsuitable as wallpapers (or maybe they are—no judgments).

Around 40% of the app's users are in China, where uploading or reposting porn can be considered a crime. The country uses a combination of AI bots and human appraisers, called Jian Huang shi, to search the web for images and decide if they contain explicit content deemed illegal.

Unlike Facebook, Google, Instagram, and many other western sites, the global version of Steam isn't completely blocked in China (there's also a version of the platform made specifically for the country).

While Wallpaper Engine is very popular among porn-starved Chinese users, the increasing notoriety of the app means the sharing of these images—or even the non-Chinese version of Steam itself—could eventually be banned.

Earlier this month, we heard about Chinese researchers who had developed a brainwave-reading porn-detection helmet. The idea behind it is to help moderators who may miss any illicit material, but with some Chinese factories already using brain surveillance devices via monitors in helmets to improve productivity and decrease worksite accidents, the implications are pretty scary.

Thanks, Kotaku