Ass fruit is basically anal fondue, where-by one person inserts small fruits (grapes, strawberries, etc..) most of, or all of the way into another person's ass and then bites or sucks them out to consume.
I plopped some fruit into my girlfriend's ass, and then enjoyed a nice little buffet of ass fruit as I sucked them out.
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.