(Spoiler Code Removed Because, Well, Thread Title and All.) Exactly. The archetypes they "cast" didn't need to perfectly fir the role just satisfy it enough for the purposes of the ritual. The Director at the end (Sigorney Weaver) admits as much when she calls Dana "The Virgin" and gets a "Virgin? Me?!" in response. "We work with what we got." Dana was "virginal enough" for the ritual and whatever manipulations they hard on her in the meantime satisfied the ritual needs. Curt wasn't really a jocky ass and the blonde girl really wasn't a ditzy slut. They were all being manipulated to satisfy those roles for the ritual.