Who is Eddy from The River Why and what is their importance?

The love of Gus's life, Gus first sees Eddy while she is fishing farther up the Tamanawis River. She is fishing in a way that he has never seen before, which immediately entrances him. He watches her from afar as she holds a fishing pole made of tree bark and shoots it through the sky once she catches the fish, racing after it on the ground before diving into the water with the fish to catch it.