The Dark Griffin (libro en Inglés) - K. J. Taylor

Being chosen as a griffin's companion has allowed Arren Cardockson to gain a place of status within the land of Cymria. But Arren can never escape the prejudice that comes with his Northerner slave origins. For chained within the Arena where rogue griffins battle to entertain the crowds, there lies another soul crying out to be freed-a kindred spirit that will allow Arren to fulfill his destiny and release the darkness in his heart.