From A Wiki of Ice and Fire
The Just Maid is an enchanted sword from the legend of Ser Galladon of Morne.
The Maiden is said to have fallen in love with Ser Galladon of Morne, who was called the Perfect Knight. As a token of her love, she gave him the Just Maid, a sword which could not be stopped by shield or sword. According to legend, Galladon only unsheathed the sword three times, not once against a mortal man, for the fight would have been unfair. Galladon is said to have slain a dragon with the Just Maid.
- ↑ 1.0 1.1 A Feast for Crows, Chapter 20, Brienne IV.