Dark Magician Girl is a character from the Yu-Gi-Oh! franchise that's often used as a card in many of Yugi's Duels, but has also appeared as a monster spirit on various occasions. She is the female counterpart of Dark Magician, another card that was used frequently by Yugi.
In M.U.G.E.N, Dark Magician Girl has been made twice by DJ Xtool and SANKITI.
DJ Xtool's version
DJ Xtool's version of Dark Magician Girl is a fairly solid character in terms of gameplay, if not a bit simple. They have the ability to teleport, as well as shoot projectiles that deal good damage. She is slightly overpowered, and her Hypers cost surprisingly little to pull off.
Their A.I. is competent, but still fairly easy to beat. Unusually, they have a small, somewhat NSFW bitmap image in their files, possibly as an alternate portrait.
SANKITI's version of the character is more unique in terms of gameplay than DJ Xtool's, but is still very similar, with the main non-graphical differences being their inability to teleport, greater variety of attacks, and an extremely powerful Hyper in which they team up with Dark Magician.
Their A.I. is on approximately the same level as DJ Xtool's, with one exception: They are considerably more intelligent when it comes to using their Hypers, frequently using them to turn the match in their favor quickly and without warning.