Sister Phantom (ファントム・シスター, Fantomu Shisutaa) is a character in the video game Flower, Sun, and Rain: Murder and Mystery in Paradise. She is a spiritual medium from the United States, who briefly stays at the Flower, Sun, and Rain hotel. She leaves on the first day of Sumio Mondo's stay on Lospass Island, explaining that she will return when her photograph is developed. Sister Phantom's only appearance in the game is during the first chapter, however her photograph is mentioned by Mondo at the conclusion of Flower, Sun, and Rain.
While she proclaims herself the best medium in the world, this is debatable as when Mondo's hotel room is transformed by a ghost, she causes a commotion over the spirit being a swirling evil force capable of possessing Mondo, when it is concluded that the spirit is in actuality a harmless ghost. While Mondo counts on her to help him with her powers, Sister Phantom disappears, having allegedly fled in a panic, although she does not admit to this when she reappears after the ghost's prank is resolved. This leads Mondo to challenge her status as a professional of her field.