The Cotton Candy Glob is a monster in the film, Scooby Doo 2: Monsters Unleashed.
The Cotton Candy Glob haunted a carnival and stole money. It tried to frighten and kill Shaggy and Scooby, but they ate him. His last words were "I'll give you cavities" as pink cotton candy bits flew across the screen implying that he was being devoured by the pair.
When he was a child his family was poor, and when the town fair came he begged his parents for some cotton candy but they could not afford it. And so when he grew up he became the Cotton Candy Glob.