After her mother's tragic death, Erin is taken in by a beekeeper named John. John teaches Erin many things about biology and zoology and introduces her to the beast known as Ohju, which Erin becomes fascinated with for the remainder of the series.
Eventually, John assists Erin in entering the premier institution for training with Ohju, Kazalm Ohju Breeding School, where she makes many friends, including an Ohju name Lilan. Normal Ohju that are raised by humans are incapable of breeding or flight, but Erin is able to overcome this by implementing her own method of raising the animals rather than the tenants of the law. This accomplishment brings the attention of Duke Damiya, who wants to use Erin's abilities to create an army that will allow him to upset the balance of power in their country.
With the help of her friends and allies, such as a Sezan soldier named Ial, Erin is able to resist Damiya and bring his scheming to the attention of the Princess Seimiyah, the current leader of their country, and his plans are thwarted.
By the end of the series it is implied at Erin and Ial have child named Jesh.