Calne Ca basically is just a sort of casing in the shape of Miku for Calcium,a Deino's original character, who is sort of a cyborg girl, (well at least in appearance, because, in essence, she is a mechanized skeleton; according to Deino, however, it is up to the viewer to decide how they want to see her, either as a mechanized skeleton, or Miku deformed.)
She is mistakenly referred to as Karune CL by fans.