Unknown has shoulder length spiky navy blue hair and dark green eyes. She wears a black sweater, a pair of gray jeans and blue nail polish. She also wears a black winter hat and she has bangs covering her right eye. When truly angered in a difficult battle she gains the Star clan eyes, which are star shaped pupils. As a member of the Star clan she possesses the clan's star symbol as a tattoo which she has on right eyelid.
Her soul is navy blue with one eye being covered and a hat.
Unknown is often viewed as emotionless. She inherited her mother's quiet tone and detatched persona. She barely tolerates her allies' personality and finds nearly everyone of them as odd, especially Black Star. Being a member of the Star clan, Unknown possesses the instinct to kill without hesitation, but she does not kill for money or souls as she claims that she kills because she is meant to be an assassin. Being left alone as a baby, Unknown lived alone and has no memory of her past or her family. As she was growing up, Unknown still killed Kishin souls and is feared by all those around her and was given the nickname "the Unknown Assassin". Until she first met her weapon, Spirit, he became fast friends with her by putting his trust in her and by playing music on his guitar. Unknown fears no one, not even a provoked Spirit nor Death or Asura.