The model has various expressions that alter its appearance. Some expressions can hide the shoes and stockings, revealing bare feet, or hide the sleeves, revealing the arms. One expression can close the shirt so that her chest does not show.
Miku Ca is a part of the five Calx sisters set (Calx五人姉妹) created by Deino. Each of the five sisters bear a color- red, blue, pink, brown, and green. Miku Ca's color is obviously green.