Casadei was a Nilfgaardian baron who was robbed by the Rats. He took particular exception to the treatment of his "sensitive" daughter during the robbery. The young woman was "relieved" of a brooch which Falka coveted and for this offence, the baron sought redress.
Later, he hired Leo Bonhart to capture Falka and bring her back to him, alive. Bonhart did capture her, but he never fulfilled his contract with the baron.