One who has sex and leaves immediately after, commonly known as a one-night stand, also a "hit and run" as an innuendo
"There are many species of sexual animals in this bar tonight. First there's the wall flower, then the emo-kid, followed by 'that guy' who thinks he can dance. Then there's the all night hammerdasher, watch closely as he stalks his next drunk target."
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.