6x22 - The Grim Adventures of Billy and Mandy

As Grim appears in an Underworld TV commercial for "Big Move" laxative pills, an accompanying contest promises a day with the famous Grim Reaper to the monster who writes the best 500-word-or-less essay describing the fun things they would do. It turns out the winner of the contest, and sole participant, is the dimwitted Fred Fredburger, who only wants to eat frozen yogurt. The Big Move company blames Grim for their sales going down since they hired him. In consequence, Grim tries save his reputation and make the best day for Fred, but it is a disaster with Grim ruining Fred's yogurt and Fred going missing in an amusement park. The Big Move executives give Grim a beating for ruining their company, and Fred finds his own paradise in a cold place with nachos- and frozen yogurt-loving creatures.