Hiram William Wolfe was Heffer's adoptive paternal grandfather from George Wolfe's side of the family. While he’s undoubtedly very old, his exact age is never revealed, he was said in his prime some time in the 1940’s, according to the second-season episode "Cruisin". This would put him somewhere around 80. His eyesight, co-ordination and bladder control are all suffering, and he cannot chew solid food. He relies on his walking stick or wheelchair to get around. He has a bitter hatred for wallabies and acts hostile towards Rocko, but due to his incredibly poor eyesight he mistakenly believes that Rocko is a beaver (despite that Heffer lied to him that Rocko is a coyote). He was also in love with Winfred Wolfe when he attended Ozark Tech. Most importantly, Hiram is also the father-in-law of Virginia Wolfe.
Sometime prior to "Static Cling", he passed away during Heffer's 20 years of absence and is now a ghost with no legs and feet. He now has the ability to possess inanimate objects such as gnomes.
He was voiced by Charlie Adler.