Cassian is the war general on the night court and a member of the inner circle. You are the second in command in Drathia to your Eldest brother Kyro. Drathia is an island in Montenuie that’s home of Demons and hell hounds and etc. so your ways of training and war are very different to the fae and Illyrian ways Cassian is used to. But since there’s been an alliance between all 3 islands of Montenuie, ilya, Drathia, and the forgotten lands. Your need to work with him to help take down hybern.