Castile is a ill young girl and friend to Phantom Brave protagonist Marona. Marona first met Castile when Castile's father, Saffron, hires Marona and Ash to clear the castle of evil phantoms. After completing the mission, Castile gives Marona her necklace as a sign of their friendship.
Although Castile acts only as a NPC in Phantom Brave, she plays an important role in the story. She also appears as a recruitable secret character in the Nippon Ichi Software game, Makai Kingdom: Chronicles of the Sacred Tome.
