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Leopold Stotch
Alias: Butters
Professor Chaos
Date of birth: September 11Eyes: Black
Hair: Blonde
Race: Human
Occupation: Grade schooler
Legal status: US citizen
Marital Status: Single
Known relatives: Chris Stotch (father)
Lynda Stotch (mother)
Base of operations: South Park, USAContinuity: South Park
Company: Comedy Central
First app.: Background: Cartman Gets an Anal Probe (1997)
Named: Two Guys Naked in a Hot Tub (1999)
As Professor Chaos: Professor Chaos (2002)
Creator(s): Trey ParkerAs Professor Chaos: Professor Chaos (2002)
Matt Stone
Country of origin: USA 
Background notes: Butters was first seen in Cartman Gets an Anal Probe from 1997 but wasn't named until Two Guys Naked in a Hot Tub from 1999.