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Harris based various elements of Gumb's MO on six real-life killers:[2][3]
Jerry Brudos, who dressed up in his victims' clothing and kept their shoes.
Edward Gein, who fashioned trophies and keepsakes from the bones and skin of corpses he dug up at cemeteries. He also made a female skin suit and skin masks.
Ted Bundy, who pretended to be injured (using an arm-brace or crutches) as a ploy to ask his victims for help. When they helped him, he incapacitated and killed them, dumping their bodies far away.
Gary M. Heidnik, who kidnapped and tortured six women and held them prisoner as sex slaves.
Edmund Kemper, who, like Gumb, killed his grandparents as a teenager "just to see what it felt like."
Gary Ridgway, the Green River Killer (still unidentified at the time of the novel's writing), who, like Gumb, dumped women's bodies in rivers and inserted foreign objects into their corpses.