When you finally get naked with someone and she slips her finger in your butthole. And you like it but you clench your starfish so tight that only one knuckle is allowed. Oh and also, it helps if your name is Drew.
I was super excited to get naked and felt really secure, until the reach around caught me by surprise. I totally got Drewgooled.
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.