Originally a member of Ms. Stevens' dancing choir 'Getting Gay With Kids', Millie has since become a minor member of the fourth grade class. She was paired with Clyde for the egg project and was one of the most notorious members of Bebe's clique during the Stupid Spoiled Whore fad. In some episodes, she speaks with a southern accent.
- "look at the little black lion."
- "I'd like to twizzle his pixie sticks!"
- "Yeah I'd like to wax his crank-shaft!"
- "I'd like ta gargle his marbles!"
- Rainforest Shmainforest (s03e01, Cameo)
- Tweek vs. Craig (s03e05, Cameo)
- Something You Can Do with Your Finger (s04e08)
- Proper Condom Use (s05e07)
- Here Comes the Neighborhood (s05e12, First speaking role)
- Bebe's Boobs Destroy Society (s06e10)
- The Biggest Douche in the Universe (s06e15, Cameo)
- AWESOM-O (s08e05)
- Stupid Spoiled Whore Video Playset (s08e12)
- Erection Day (s09e07)
- Marjorine (s09e09)
- The List (s11e14)
- Eek, A Penis! (s12e05, Cameo)
- Super Fun Time (s12e07, Cameo)
- Breast Cancer Show Ever (s12e09)
- Elementary School Musical (s12e13)
- The Ring (s13e01, Cameo)
- Medicinal Fried Chicken (s14e03, Cameo)
- Funnybot (s15e02, Cameo)
- T.M.I. (s15e04)
- The Poor Kid (s15e14, Cameo)
- Butterballs (s16e05, Cameo)
- Cartman Finds Love (s16e07, Cameo)
- Insecurity (s16e10, Cameo)
- A Scause For Applause (s16e13, Cameo)
- Let Go, Let Gov (s17e01, Cameo)
- The Cissy (s18e03, Cameo)
Millie can be found behind a building, in which you have to destroy a snowman to get to her and befriend her. It is revealed she smokes.