Many moons ago, I’ve read a translation of a Japanese short story, which stipulated that a pastime among Japanese youth is having one person reportedly lick an eyeball of another, whereupon the recipient begins experiencing special effects, iirc described as seeing diamonds in the sky.

As an aficionado of various psychologically surreal shit, I’d be glad to find this story again, but the chances are slim. It might’ve been written by Kobo Abe, as I discovered his work at about the same time and space, but I have doubts about that.