Erza Knightwalker is part of the Edolas Kingdom and is a Royal Army Captain of the 2nd Magic War Division. She is the Edolas counterpart of Erza Scarlet. Her counterpart's surname, "Scarlet" was replaced with "Knightwalker".

Unlike her Earth Land counterpart, Edolas Erza is sadistic, cruel, and would kill with a smile. Showing no sympathies towards her enemies and kills without mercy, she had been involved in killing over half of the members of Edolas Fairy Tail, thus earning the title Erza the Fairy Hunter. She seems to take great pride of this title bestowed upon her; as a result, she took it as a personal insult when Lucy told Knightwalker that her Earthland counterpart happens to be a staunch ally of the Earthland Fairy Tail Guild whose loyalty to her friends was also unquestionable. This led to her becoming more hostile than she already was towards Lucy, she even opted to kill her by dropping her from a great height.

Knightwalker also appears to value her pride as a Captain for the Royal Army; and Charle making her prostrate herself by kneeling down to the floor seemed to be a real blow to her ego that when Pantherlily informed her of Happy and Charle's rebel status (and that was made even worse by the fact that Charle wheedled information from her only mere moments ago regarding the location of Natsu and Wendy through trickery by claiming to be the daughter of Shagote), the latter became the first whom she targeted to kill. However her streak of fighting has made her overly arrogant and she doesn't seem to take losing lightly as seen when Erza Scarlet managed to temporarily beat her off screen.