A bizarre trend in Japan is proving that kissing and canoodling can be all fun and games until somebody licks an eyeball.

The trend involves prying back the eyelids of ones you love to lick their eyeball. The practice, dubbed “worming” or, more clinically, “oculolinctus,” might sound harmless -- if somewhat gross -- but it appears to be leading to a spike in eye infections.

According to some who have tried eye licking, it can induce erotic sensations, much like another notorious germ-spreading mode of affection: toe-sucking.

One woman named Elektrika Energias, told the Huffington Post she’s hooked on the habit.

"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 said. "I just love it because it turns me on, like sucking on my toes. It makes me feel all tingly."

But the practice is also a great way to spread mouth germs that have no business being on the eyeball. And those germs can lead to an eye infection called conjunctivitis, better known as “pink eye,” says Dr. Tanya Sitter, with the Canadian Association of Optometrists.

“Most colds and flus and some other infections are spread by saliva, so it’s not surprising that if you’re applying saliva directly to the eye, you’re going to see an increase in bacterial or viral conjunctivitis,” she told CTVNews.ca from her office in Olds, Alta.

Sitter, who admits she had never heard of “eye-licking” until this week, says even more concerning than pink eye would be the risk of transferring serious pathogens, such as chlamydia bacteria or herpes viruses.

“You’re putting yourself at risk for any kind of infection that can live in your mouth,” she said.

“You can get a herpes infection of the eye. So cold sores in your mouth, they can transfer herpes to the eye. And those infections are incredibly painful and not easy to treat.”

It’s also possible to develop a form conjunctivitis caused by chlamydia bacteria, called trachoma.

“That’s a pretty nasty one,” Sitter says.

The issue of infections caused by eyeball licking was first exposed by the Japanese website Naver Matome and then translated into English this week by another website called Japan Crush.

In the Naver Matome post, a Japanese middle school teacher identified as "Mr. Y," said he had been noticing that kids in his Grade 6 class were often coming to class with styes, or bumps on the eyelids caused by mild bacterial infections. Then he noticed that as many as 10 children in the same class were wearing eye patches.

He figured out what was going on when he stumbled upon a young couple in a supply closet at the school who were licking each other’s eyeballs. The students were questioned and eventually revealed that eyeball licking had become popular among their classmates.

As for how the trend got started, it’s unclear. Some are pointing to a music video released earlier this year by Japanese band Born in which a woman licks the eyeball of the band’s lead singer.