It is unlikely that Ferrer was her pimp as it is usually understood. It looks like that the state wants to charge him as a pimp because he provided a venue for sex workers to advertise and therefore was effectively doing promotion. It is unclear at this point whether the court will agree with that interpretation or not. I am sure the 15 yo was brought into the charging documents as a sob story for the public (and later the jury) and to pressure the accused to make some sort of a plea deal.