Leopold "Butters" Stotch

Leopold "Butters" Stotch (voiced by Matt Stone) is a fictional character in the animated television series South Park; his nickname is a play on the word butterscotch. Butters has a large tuft of blond hair on top of his head, and wears an aquamarine jacket with green pants. His birthday is September 11, after the September 11, 2001 attacks.[1] Having a birthday that's the same day as a national tragedy is one of the many misfortunes Butters has suffered. Butters speaks with a distinctive stuttering Southern accent, and has a wholesome attitude despite suffering greatly at the hands of his friends and family. The character is loosely based on South Park director of animation Eric Stough, who Parker and Stone regarded as a "goody-goody" because of his reluctance to offend.[2]
The creators have said in multiple DVD commentaries that Butters is one of their "top 3 favorite characters".