Who is de l'Orme from The Descent: A Novel and what is their importance?

de l'Orme is a former priest, who spends his life researching ancient peoples. As a blind man, he is often assisted by his lover, and he is good friends with Thomas. it is de l'Orme who discovers that the Shroud of Turin is more than likely a likeness of the devil. At the end of the novel, de l'Orme is murdered by Thomas after killing his lover.