Calvur was the head of the criminals that carried out Prince Attrebus' kidnapping.
Hierem hired Calvur's men to kidnape the prince and make it look like as if it was a murder. Arese visited Calvur because someone knew she had failed to pass on Gulan’s warning to the Emperor and was blackmailing her. Calvur offered to deal with it at no extra charge. Arese told him they could do anything to solve the situation. The conversation heated and Arese summoned a daedra. The daedra killed Calvur and his thugs.