When revealed it has the form of something like a man, eyes wrapped as though blind, mouth pressed shut, still it is difficult to distinguish a full form, things seem to simply get lost in the space between where one part is and where the next should begin.
Anima's true form has not been seen for many years, truthfully it can not be seen, a remnant of the shackles that once bound it to Aris. It's true form is still trapped on the world in which it was created, though the very being is free to move where it wishes

History
Anima. Chaos.
It is well known that the world consists of "Angles" and "Demons", creatures of power beyond that of mortal beings. Anima is not one of those. It was created in a place called Aris by certain "Angles" in an effort to protect their world and those mortals who lived in it from a particular "Demon". The resulting being did its job, though it did so at the expense of many lives and nearly the world itself. Anima did all it could to combat it's enemy, but its creators found that it served this singular goal despite the damage it did to that which it was supposed to have been created to protect.
War ensued.
At the end Anima somehow came to Attello Hasting, a dying soldier, a hero of his time, and joined its being to the mans soul. This broke Anima's bind to Aris as Attello was not bound to the world, and it gave Attello immortality as Anima was not bound to time and death.
Anima, free of its former goals continued in the one thing it reveled in, chaos. This wasn't always on a grand scale, and over many years its connection with a human host had begun to mildly shape its actions, if it had any sort of goal now it was the protection of that which allowed it to move from world to world, unbound by time and space. This connection also places it under some authority from Attello, knowing that while Attello didn't possess the knowledge, he was capable of ripping himself from Anima.
Powers and Abilities
Anima does not possess a physical body out side of Aris, but this does not diminish his power as even on Aris he rarely used his physical form. The true power of Anima is the ability to create physical effects mentally. This includes what many refer to as magic. But this ability is more than simply magic. Anima sees, speaks, hears, and and feels mentally. Every interaction is a manifestation of its thought.
Combat: The most basic form of combat for Anima involves causing physical pain via mental stimulation.