Who is Nestor Noralez and Barbara Villanueva from Dogeaters and what is their importance?

Nestor Noralez and Barbara Villanueva are Manila radio personalities, the stars of the radio soap opera Love Letters. In the world of the play, these two characters serve as chorus to the action, narrating it as they would the soap opera. This gives them otherworldly qualities, like the ability to interview a nineteenth century Jesuit priest.