Just watched the Fantastic Mr. Fox, the movie based on the Roald Dahl children's book. The movie was rated PG for action, smoking, slang humor. Slang humor = substituting, for example, clustercuss for cluster___ You get the idea.
"Throughout the film, the word 'cuss' is used in place of actual cursing. When asked about its origin in a radio interview on 'Fresh Air' with Terry Gross, Wes Anderson said, 'I don't even remember. It think it was just to use the concept of profanity as a replacement for profanity itself. It turned out to be very versatile.' In keeping with this theme, one of the buildings seen in the film bears 'CUSS' written as spray-painted graffiti." http://www.imdb.com/title/tt0432283/trivia