Lou appears to be a young girl with curly red hair and bright yellow eyes. She wears a maid dress reminiscent of the Victorian style, with dark sleeves and a white apron and skirt. She often has a black bow in her hair.
Lou is a quiet and obedient girl who listens to her master's every order. Her top priority is taking care of Louise and her own safety. She often gets worried about her face getting damaged and has been known to invade in people's personal space. When she sets her mind to something, she's very determined to achieve it, especially if it has to do with Louise. Unlike Emilyko she doesn't think of "unnecessary thoughts" and has the potential to be an outstanding Living Doll.