"The internet is full to the rafters with animal penis stories, popular science pieces about animal penises and listicles about animal penises,” Jules Howard, science educator and creator of the app, explained in a Twitter thread . “It's a bit depressing.”

I played VR Duck Genitalia Explorer , a new virtual reality app for exploring the strange, twisting world inside of a duck’s vagina. It’s like the Magic School Bus, but for the inside of a waterfowl.

As we begin the VR experience, Brennan shows me a few photos of ducks—standing, mating, generally chillin’ out—while a CGI duck stands in the “room” in front of me and preens. Next, I’m introduced to what looks like a statue mold of a duck’s vagina, again, while the duck herself stands by. Kind of awkward to have her watching me, but she seems unbothered.

The VR experience is narrated by Patricia Brennan, a professor of biological sciences at Mount Holyoke University who says in the app that she’s particularly interested in muscovy ducks. “I think it really brings to light how complex these vaginas really are,” Brennan told me in an email. “The muscovy ducks were the species that was typically trained by farms for sperm collection. Because I study genital evolution, having animals trained in this matter was very useful. Muscovy ducks are also fairly promiscuous, so that is another beneficial thing about them.”

There might be a bias toward weird animal dicks over equally-intriguing vaginas because “vaginas are internal structures and not bibbling around and exposed and everything,” he said. It’s a correct observation: Lots has been written about the corkscrew pig dick , the mallard duck penis, and the echidna’s four-headed penis. We gawk at these because they’re so foreign from what human sex organs look like, but what about female anatomy? Female animal genitalia is often just as bizarre as their corresponding dicks.

After these few opening scenes where Brennan teaches me about duck vaginas from the outside—including a horror-movie quality black and white video of a duck penis entering a duck vagina—we’re ready to enter. And enter we do.

I’m proud of this duck, actually. Each twist and turn inside this labyrinthine reproductive system is a new challenge, to be met only by the most worthy mate.

I’m faced with a cavernous greyish path ahead of me, propelled forward with red arrows through the vag like I’m on a rollercoaster. The inside of a duck feels a bit claustrophobic, but Brennan soothingly tells me that what I’m seeing are a series of blind turns, followed by spirals. There’s a pouch in the entrance that the male penis must navigate around, but most times, the penis gets stuck at this impasse, giving the female more control about who impregnates her.

After I exited the vagina, I emailed Howard and asked why he chose virtual reality for this experience.

“We kind of felt like VR might lend itself well to this form of immersive storytelling,” he told me in an email. “Plus, Patricia and her team had a 3D scan of a duck vagina, which I knew could be inserted into a 3D world really nicely. We shrunk the viewer down, inserted the 3D vagina model, programmed the journey and then... voila.”

“I think apps like this one can really serve two functions: one is to really allow folks to visualize complex structures that may be too difficult to grasp with 2-D, and two, to get people who normally may not be interested in science, to start asking questions about interesting biological phenomena by stepping in the VR novelty,” Brennan said.

Choosing an Android launch that students and classrooms could use with Google Cardboard seems like a good fit for educational purposes, Howard said—but he was a little concerned that it would run up against issues on the Play store. It is a vagina explorer, after all. But it was accepted without trouble. “This is cool science. It's an educational app that really has a message. We're really hopeful people use it.”