Arthur Frilan is a non Cahill member who had a war with the original Cahill members and really won since he had killed mostly everyone on the opposing team. He has two kids and a wife none of which are the same as his evil rude ego. He is known to have anger issues and no he is not associated with the Vespers as he thinks that he himself is the entire Vesper commitee. The reason he decided to destroy the council was because he heard that they tried to hack into his group database and delete all of the information but they did not succeed in it. His people didn't really want to destroy the council but they certainly didn't want it to be in existence but they obviously had no choice or else they would die.