1 definition by JellyDoesMC

Ejaculating an unfathomable amount of cum on a human males back, typically after engaging in homoerotic activities with a male (or trans male).

The word is stemmed from the phrase "light up my back."
“Dude, how was Thailand? Did you get any of their cheap sex massages?"

"Naw dude, I paid them extra to gyl me! It was awesome!"
by JellyDoesMC July 6, 2022
Get the GYL mug.