Nanana Ryugajo is a central character in the anime series 'Ryuugajou Nanana no Maizoukin.' She is a ghost bound to Room 202 of the Happy House residence after being murdered. Nanana is lively, intelligent, and has a fondness for pudding. Her role in the series is pivotal as she guides the protagonist, Juugo Yama, in searching for the mysterious treasures she left behind, known as 'Nanana's Collection.' These treasures hold special powers and are key to unraveling her murder mystery.