The protagonist of "Phantom Brave" is a 13-year-old girl named Marona. Having lost both of her parents at a young age, Marona lives on Phantom Isle in the oceanic world of Ivoire with a phantom named Ash. While he was still alive, Ash worked alongside Jasmine and Haze (Marona's parents) as a Chroma, a sort of bounty hunter or adventurer for hire. On an assignment that brought the trio to the Isle of Evil, a fragment of a malevolent being known as Sulphur attacked the group, mortally wounding them. Using the last of his life energy, Haze attempted to revive the party after the battle; however, there was only enough life left in him to bring Ash back as a phantom. Haze and Jasmine's dying wish was for Ash to watch over their then infant daughter Marona.