sentences:  Bergman was originally listed in the credits under the alias Shannen Cassidy to protect her reputation as the voice of several Disney and other kid-friendly characters.Stewart was originally credited under the name Gracie Lazar, while Schneider was sometimes credited under her rock opera performance pseudonym Blue Girl.Other voice actors and members of "South Park"'s production staff have voiced minor characters for various episodes, while a few staff members voice recurring characters; supervising producer Jennifer Howell voices student Bebe Stevens, co-producer and storyboard artist Adrien Beard voices the school's only black student, Token Black, writing consultant Vernon Chatman voices an anthropomorphic towel named Towelie, and production supervisor John Hansen voices Mr. Slave, the former gay lover of Mr. Garrison.