Eve's orginal appearance is unknown.
Her appearance after having been brought into existence by the Geass Order, who used Akashi Shiba to do so, has greatly been influenced by Akashi's own physical features. Her hair is a soft pink, a few hues darker than Akashi's, and reaches the ground. Her eyes are a dark fushia pink. When she is brought back by the Order she is naked but is later given a dress that resembles that of a ballerina's.
Despite her rather sweet and gentle appearance Eve is rather sadistic, enjoying that she can toy around with Lelouch's feelings, and finds great pleasure in causing the children living with the Geass Order great pain, even going as far as making them commit suicide in order to drink their blood. Because that she has taken over Akashi's body a bit of Akashi's personality still remains within Eve's soul as Akashi was the foundation for her recreation. Especially Akashi's devotion to Lelouch refuses to leave her body which more than once has interferred with Eve's desire to kill Lelouch since she sees him as nothing more than an obstacle for Adam.