They are the eighteen-year-old leopard girls who serve as soldiers under Folken's command. Naria (the older of the twins) is the silver one and Eriya is of course the gold one. Folken rescued them from a mob of humans when they were eight-years-old so it is only natural that they have an attachment to him. Folken uses them to work his fortune (or luck) altering scheme, but eventually in the end they die.