Shockingly, people are into sex — even if it’s virtual.

Searches for “VR porn” have increased 100-fold from November 2014 through April 2016, according to Google Trends data (via VRTalk.com). That is growth of 9,900-percent in 17 months, and it shows how rapidly an idea can take off if it involves new ways to look at naked people. Analysts at research firm SuperData predict that virtual reality could turn into a $40 billion business by 2020, and the demand for virtual porn is more evidence in favor of that outlook.

Image Credit: Google Trends

The idea that porn is important to new technology is conventional wisdom. You’ll commonly read that VHS beat out the superior Betamax in the video-cassette format war because pornographers chose VHS. The truth is likely more nuanced. Adult films weren’t the only deciding factor because they were only a tiny portion of the market even back then. But the XXX industry definitely played a role in how some people adopted and used their expensive new entertainment devices in the late 1970s and early 1980s.

Sexual content obviously has a similar effect on the ways people use the internet and connected devices like computers and smartphones.

Now, as virtual reality is struggling to bloom into a viable marketplace, the Google Trends data highlights that people are once again thinking about what the next generation of tech can do for their libidos. And that’s likely a good sign that people already know why they want a head-mounted VR display.

360-video vs. interactive porn apps

People want porn in VR, but most don’t know what that even looks like.

The Oculus Rift and HTC Vive headsets that plug into your PC as well as mobile solutions like Samsung’s Gear VR and even Google Cardboard already have a lot of adult content. Sony’s upcoming PlayStation VR should work with some of that content — although you can expect limitations that will hold the device back. The majority of this involves traditional actors working on a set in front of a 360-degree camera. Pornhub has launched a NSFW site dedicated to serving these kinds of VR videos, and it works with just about any headset.

Here’s an example of the kinds of 360-degree video that are already on VR devices (consider all videos NSFW):

360-degree video, however, is only the beginning of virtual porn, and the results so far are strange. These movies often have a bizarre sense of scale that makes the actors look inhuman. I’m sure that’s someone’s thing, but a lot of people are going to find it creepy.

Video is not the only method of delivering adult VR content. Instead of putting a static film over your eyes, developers are already working on building fully interactive environments where you can walk around and import dozens of characters. That kind of interactive XXX app makes a lot more sense for VR. The benefit here is that players will have a lot more control over what their simulated partners look like and do.

For example, here’s a fan unofficially importing the digital character Hatsune Miku into their Oculus Rift:

Of course, VR sex games are not ideal either because it’s difficult to build a character that looks human — although this NSFW video shows that graphics engines like Unity are making that possible.

Even with the “uncanny valley” and skewed first-person perspectives in the way, 360-filmmakers and XXX-game developers will keep working on this problem. The demand for VR porn will see to that.