Maha or Macha is more of a mystery than Aura I belive..her lips move as she speaks but there is no sound to hear, Tsukasa seems to know what she says though,
Maha seems to tease and taunt Tsukasa which only is discribed as a mime..and Maha's intentions are not clear.

Maha is chased though out the world by the scarlet knights because no one is allowed to mess with their charaters appearence.
Since she had been seen with Tsukasa, the scalet knights chase down him for answers but he did not reveal any thing about him or the cat-like creature.
Morugana is the one who created the Cat-like creature to destroy Tsukasa and his friends...

Name : Morganna Mode Gone, or ' The Voice '
.....Voices .....
Japanese ; Rie Tanaka
English ; Valerie Arem

Morganna is the most strangest character in .Hack//Signshe keeps telling Tsukasa that the real world all that waits for him is lonliness and pain, and that the world is the only place for him.
She was also responserble for the guardian, and terrorizes and comforts Tsukasa appearing as a motherly voice, this entity is also the reason why Tsukasa can't log out.