Pubby

Pubby is Grubby and Herbert's grandfather and the Ubbian drunk. He was banished from Ubby to Earth for his drunken shenanigans in the 1970's. He eventually fathered two children, one half Ubbian (Herbert's parent), and the other full Ubbian (Grubby's parent). Pubby then just lived his life in a booze filled haze until Grubby and Herbert found out about him and met him in "The Duo Becomes Hip". Every once in a while his grandchildren come to visit him, but other than that he's not very important to the story...