Grampu is an old man. He lives with his two grandkids, Oobi and Uma. Their parents and grandma are never seen or talked about, so Grampu is the only one who takes care of them. He likes to teach them about the world. He shows them how to do new things. As a running gag (repeated joke) in the show, Grampu is very unlucky and usually has to clean up messes that the kids make.