The console version of The King of Fighters XII has two extra characters. And no, Mai isn’t one of them. Elizabeth Blanctorche from KOF XI and Iori’s partner in crime, Mature, bump the roster to 22.
No word if the will be the last additions, but a screenshot of the roster doesn’t leave any extra spaces for speculation. Of course, SNK could hide Mai and K’, which have KOF XII style art, in an existing space or, perhaps, sell them as downloadable content.