Unko is 18-years-old, a third-year student, and president of the Shimoshina student council. She is an energetic girl and is very intelligent. Due to her fear of ghost stories, she prefers to be referred to as Unko (a homophone for the Japanese word for feces) rather than Sadako, the correct pronunciation of the kanji that make up her name.
Her name "Unko" though may have a homophone for "Feces" actually means "Lucky Child."
(Source: Wikipedia)