Alias: Sarah Frost
The name given to a serial killer hunting the homeless in and around Rat City. Spawn, the police, as well as Sam and Twitch hunted the murderer as his victims added up. As it turned out, the Exterminator was a woman named Sarah Frost who had been coaxed into killing by the ghost of Billy Kincaid.
Dr. Sarah Frost was a "Client Liaison" for Saving Grace Community Outreach Center. She sought to help the homeless and disadvantaged by helping them get started on a road to recovery. When she became possessed by Billy Kincaid, however, she became compelled to "dispose" of those who refused her helping hand.
After her murderous deeds, her soul was damned to Hell despite being possessed. A mark was left on her neck indicating "Diabolus Interium", the method Kincaid used to control her.
Before Spawn knew of Kincaid's involvement, he tortured Sarah with her greatest fears (insects and dirt) until she committed suicide unintentionally by spraying pesticides into her face and throat.