Nancy Greatjohn, born Nancy Whaler, is a human female native to the country of Tywrought, a citizen of the Tyrannian Empire. She is the daughter of Alfred Whaler, a merchant who made his fortune in the trading of fishery, and was married to the adventurer Karstone Greatjohn some twenty years ago. Although the two are estranged, for Karstone has never given up his day job of heroism, Nancy cares deeply for her husband and remains faithful to him, even if their relationship is more amicable than romantic.

Together, Nancy and Karstone had a son, Railon, whose tutorship has been paid for by Karstone's adventuring winnings, and who has been raised into a healthy young man by Nancy herself.