Arianna is a fairy princess left hidden with a human couple named Reed and Rose Rivers when she was just a baby in the small town of Bellmont. The Fairy realm is under attack by a Dark Fairy named Aliri-on, who is intent on ruling over the whole realm.
Arianna grows up living an ordinary life, not knowing about her true identity. Her secret identity is shortly forgotten. After her sixteenth birthday, she accidentally meets Caspian, a fairy from her realm. In the meantime, the Alirion escapes and threatens the safety of the realms again. Arianna joins Caspian in the Fairy realm, along with her true family, to fight against the Dark Fairy.