Since the beginning of South Park almost 30 years ago, Eric Cartman has been one of the absolute worst people in the small Colorado town. He's used all sorts of people as tools for his plans -- none moreso than the perpetually put-upon Butters Stotch. But Cartman and Butters' dynamic shifted in Season 26, as Butters experienced more personal growth.
Source:https://www.cbr.com/south-park-season26-butters-and-cartman/