Erin has an interesting occupation: she's what's known in the advertising business as a "parts model." In Erin's case, the "parts" are her feet. Her feet have no scars, blemishes, tattoos, or visible calluses. Her toes are straight and evenly spaced. She has well-proportioned arches. Her feet have an attractive nail bed shape. Erin's feet, according to several advertising executives, are "flawless."