Phantom Girl is a slender girl of medium height, with pale blue skin and neck-length straight black hair. Her eyes have black sclerae and red irises. 

She wears a formfitting jumpsuit, covering her entire body from neck to toe, with a hood attached to her shoulders. The suit is almost entirely white, except for the black area around her neck and above her chest, with a white "P" on it, as well as black gloves. On her right hand she dons a golden ring with an L-insignia.