Your explanation will be cited by Merriam-Webster as the origin of "grass" in a few years.[/quote]It all started when tim threatened to grass viper's sister.
1111. Well, what is the meaning of "grass" as a verb? ops:
It's a term originally coined by Tim and means something like "beat/defeat/rape". Tim's English is nothing short of extraordinary and when he and Viper were exchanging compliments, Tim felt that the conventional vocabulary was just too restricting and instead exclaimed: "I grass your sister".
I think "grass" in the context of "grass your sisters" means tim wants to go muff diving on viper's sister. Since its very uncommon for chinese ladies to "mow" or "trim" their "lawns" whatsoever. Therefore, for Tim "grass" refers to a womans lawn. Tims offering to "grass" or graze it, since he knows western women usually do trim their lawns and it can be quite costly to do.
So tim comment was actually just a misinterpretation, he was just trying to help.