when ur friend invites you over to your stepmoms house and she makes you grilled cheese with a note "meet me upstairs, daddy ;)" you quickly yeeted up the stairs to the laundry room to find your grandfather sucking the gay neighbours dick.
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.