The underworld counterpart of Yu Kamimura (上村 優 Kamimura Yū) is a mysterious young woman who lives in the Underworld, appearing in the film Kamen Rider × Kamen Rider Wizard & Fourze: Movie War Ultimatum. She is the alter-ego of Young Masked Belle Poitrine (美少女仮面ポワトリン Bishōjo Kamen Powatorin) and the Underworld counterpart to Donut Shop Hungry Manager.