From A Wiki of Ice and Fire
|Book(s)|| A Game of Thrones (Appears)|
A Clash of Kings (Appears)
A Storm of Swords (Appears)
A Feast for Crows (Mentioned)
A Dance with Dragons (Mentioned)
Elmar Frey is the youngest son of Lord Walder Frey. Elmar is the twenty-second born son of Lord Walder Frey and the fourth son born of Lord Walder's marriage to Annara Farring. There is a rumor in the Twins that Annara Farring was sleeping with Black Walder Frey, casting doubts on Elmars parentage.
A Game of Thrones
A Clash of Kings
Elmar squires for Lord Roose Bolton and is part of his army when it takes Harrenhal. It is at Harrenhal that Elmar learns that his betrothal is called off. Unbeknownst to him, his princess, Arya, is standing before him.
A Storm of Swords