Callie Maggotbone is a character in the Ugly Americans TV show. She is a character in the game based off the TV show too, entitled Ugly Americans: Apocalypsegeddon.
Callie's mood tends to change very often and drastically, resulting in her breaking up and getting back together again with Mark very frequently. Mark once referred to this as being "more schizoid than normal."
She is extremely sadistic, occasionally hurting Mark and getting turned on by violence given to others.