Fiona is a ghost from Ghost Story Island. As the island progresses, it is revealed that the central plot of the island revolves around her past.
Fiona had a love named Valiant, and was a friend of Henry Flatbottom, who would later become the Magistrate. At some point Valiant proposed to Fiona, and she accepted. Henry, being in love with Fiona himself, was deeply jealous and wanted Fiona for himself. He devised a plot to send Valiant away from Hemlock Harbor, making him think Fiona was no longer in love with him; in Valiant's absence, he bought a ring and proposed to Fiona himself. But she refused him, even throwing his ring in the fountain in the square. She passionately preferred to wait for Valiant to come home, and she waited, not knowing the truth about why he had gone. When he did not return, Fiona pined away of sadness and died. Yet even in death, she remained in her room, watching out the window and awaiting her lover's return.
Most people know her as the Woman in the Window. After obtaining the violin and playing it, she appears in the window and beckons you closer. You climb up the cliff and go inside the cellar, from there you navigate to the top of the house, you find a telescope, you look in it, and when you close it she mysteriously appears behind you. She claims to not be a ghost and tells you to go to the Gingerbread House and tell the baker, Jane that she sent you. You go to the Gingerbread House, and tell the baker. The baker then gives you gadgets, which you later utilize to hunt down the other ghosts. After you discover the story of Flatbottom and Valiant, the Cemetery Specter appears and you reveal him to be the Magistrate. The Magistrate claims he is truly sorry for those he had wronged. Fiona then appears before you as a ghost, along with the other ghosts and accepts his apology. She and Valiant are then reunited and the two rest forever in peace along with the other ghosts.