When you are going down in your brother and you pull your cock out of him and shoot your load on your baby brothers chest while making intense eye contact with your dad.
Me and my family had a dirty Greyson the other day.
A Dirty Greyson occurs when you inject Boar Semen into both of your ears, let it crust, and then proceed to have your sexual partner scrape the semen crust out of your ear while grunting to that of a wild boar.
Duuuuuude, I can still feel the crust in my ears from that sick Dirty Greyson we pulled last night
A trip to a grocery store, convenience store, or gas station for the sole purpose of buying an excessive amount of junk food and sugary drinks, usually with friends. A chud run often happens late at night and ends with everyone involved hating themselves afterwards.