Mandy is the deuteragonist of the franchise, who is friends with Billy and Grim. She is a perpetually cynical, merciless girl from Endsville. Sometimes she serves as a protagonist of the show. In stark contrast to her cheerful, talkative, uniquely stupid best friend Billy, she is shown to be intelligent, quiet, bitter and utterly ruthless.
After the theme song, Mandy is shown in front of a black screen, usually speaking to the viewers in a creepy, sarcastic way, similar to the couch gag opening of The Simpsons.
- Emily, Daisy or Elizabeth (Thomas)
- Blaze the Cat or Amy Rose (Sonic the Hedgehog)
- Edna Krabappel (The Simpsons)
- Princess Peach or Birdo (Super Mario Bros)
- Toots (Tom & Jerry)
- Buttercup or Bubbles (The Powerpuff Girls)
- Eleanor (Alvin and the Chipmunks)
- Pearl (Spongebob)