Have Sword, Will Travel (Have Sword Will Travel, 1) [Nix, Garth]

Odo is the seventh son of the village miller and he just wants to get away from work for awhile, Eleanor's mother was a soldier, and she yearns for adventure, but it is Odo who finds the magic talking sword named Biter, and thereby instantly becomes a knight--and together they set out on a quest (somewhat reluctantly on Odo's part) to save their kingdom from threats both human and dragon.