When you do a girl anal and you get that shit thats green on your dick and you cockslap her in the face with it.
Guy1:I grass stained my girl last night
Guy1:I broke up with her afterwards
Guy1:she liked it.
After having sex with a girl with ghonnorrea, she leaves green marks on ur bed, or other place of sexual activity..eg ironing board
Shit girl, u left grass stains on my ironing board...
1. The level above a pot head or stoner. One who smokes unhuman, almost extraterrestrial amounts of marijuana.
2. A way to explain one's state of mind when extremely high.
1. Yo Fred you're a straight up grass stain.
2. I'm so grass stained right now I feel like I have to mow my hair.
ejaculation on the pubic hair of a woman
"that shieet be so tizzight, i had to leave the girl a grass stain."