Booste is a Boo living at Creepy Steeple, and one of the partners in Paper Mario: The Thousand-Year Door 2. He was living in Creepy Steeple with the other Boos when Mario first came to Creepy Steeple in search of Vivian. When Mario first asks him to join with them, he flatly denies, being nervous by nature as most Boos are. But when the perdicament comes clear, he readily joins.