Who is Demetrius Aldous, the Eritrean Father, the Papal Special Rep from The Autumn of the Patriarch and what is their importance?

Demetrius Aldous, known as the Eritrean, is the Pope's special representative. He is sent to the nation after the Pope agrees to investigate the claims to canonize Bendicion Alvarado, the General's mother, as a saint. The Eritrean is a friendly man, who mixes well with the common people. Over the course of the novel, he certifies and takes sworn statements regarding the miracles of Bendicion Alvarado. He also makes an investigation of the interior of the nation to get the General's and Bendicion's birth records and other records. He later asserts to the General's face the total fraud of the operation to canonize the General's mother. In retaliation, the entire Catholic Church is expropriated, and its clergy is expelled.