A dangerous fetish has eye experts seeing red and those who practice it seeing pink.
It is eyeball licking -- a strange erotic activity wherein participants actually put each other's tongues on each other's peepers.
Alternatively called "oculolinctus" or "worming," eyeball licking has few public advocates but they include Elektrika Energias, a 29-year-old environmental science student in the U.S. Virgin Islands.
"My boyfriend started licking my eyeballs years ago and I just loved it. I'm not with him anymore, but I still like to ask guys to lick my eyeballs," she told The Huffington Post. "I just love it because it turns me on, like sucking on my toes. It makes me feel all tingly."
It's also a very intimate act, she said.
"I don't ask just anyone to do it. Guys I like a lot are more likely to not think it's so weird. I've never had anyone turn me down though," she said.
Eyeball licking has been around at least since the mid-2000s and a simple YouTube search brings up hundreds of videos from oculolinctus lovers who want to share their peeper porn with others.
However, eye experts are worried that this dangerous fad is gaining popularity with preteens, especially after news reports of elementary school students in Japan who dared to test their ocular boundaries and caused multiple cases of pinkeye, otherwise known as conjunctivitis, the Daily Caller reported.
In one classroom of 12-year-olds, one third of students confessed to "worming" or being "wormed." Officials only noticed something was up when some of the licked students showed up to school wearing eyepatches, ShanghaiList.com reported.
Currently, eyeball licking is only attempted by a small percentage of adventurers, including HuffPost Weird News journalist Andy Campbell, who said he had his own eyeball tongued to see what it's like.
"It's strange to have something touch the eye without it hurting," Campbell said. "I was a receiver, not a giver. I don't see it as a sexual thing. But you have to be comfortable with someone."
San Diego ophthalmologist Dr. David Granet are worried that the news of eyeball licking will cause it to spread.
"Nothing good can come of this," Granet warned HuffPost. "There are ridges on the tongue that can cause a corneal abrasion. And if a person hasn't washed out their mouth, they might put acid from citrus products or spices into the eye."
Dr. David Najafi, an ophthalmologist in La Mesa, Calif., said if the licker has a cold sore, it is possible to spread herpes into the eye as well.
"The cornea is very sensitive and could be scarred," he warned.
Other dangers from "oculolinctus" include conjunctivitis or "pink eye," a swelling of the thin, filmy membrane that covers the inside of the eyelids and the white part of the eye.
You might have been the old superstition that masturbation causes your vision to blur, but eyeball licking can actually cause blindness, according to Dr. Phillip Rizzuto, a spokesman for the American Academy of Ophthalmology.
"The bacteria in the mouth is nothing like the bacteria in the eyeball, which is why we no longer recommend people lick contact lenses to moisten them," Rizzuto said.
Those serious problems may not be enough to stop eyeball licking lovers like Energias, who admits her habit did put her eyesight at risk at one point.
"I got some weird offshoot of TB in my eye once. I ended up with corneal ulcers and I spent like a month in the hospital," she said. "Nobody really knows why. Well, I got over it, and I'm fine now. That was like six years ago.
"I'm just safer now, I guess ... Live and learn. I mean they don't really make tongue rubbers, but maybe they should."