How does Berkmann describe Kali? Why was she in Harper's house?

On the tape Berkmann made for Harper, he describes Kali as his faithful concubine of twenty years. He blames Harper for her death. She was jealous and angry over the interest that Berkmann had taken in the persona that Harper created - "Erin". She accompanied Berkmann to Harper's house because they traced the online activity to that location. Neither of them had expected to find Erin there.