Nerasin was a Duke of Asturia during the 24th century, and a large thorn in Polgara's side during her campaign to end the Arendish Civil War. The nephew of Duke Oldoran, he was prevented from succeeding his elderly uncle when Polgara and her allies Mangaran and Asrana had the old man ousted under false pretenses, resulting in Mangaran seizing control of the duchy. However, when Mangaran died a few years later, Nerasin successfully prevented his chosen successor, Olburton, from taking over, and thus forced his way back into power.