The old man is short, having white hair with silver streaks, a long full beard, a balding head, and turquoise eyes. He wears a light gray shirt with long sleeves underneath a light blue vest, brown jeans, and black shoes.
In "The Princess Most Fair", in Larry's flashback at the laundromat, the old man appears as an employee or manager there, suggesting that it used to be his job when he was younger.
According to Larry in "Larry Manor", the old man gave him a peanut plant, which grew a peanut that was the first Larry fed to his pet elephant Tony.
According to Sam Levine, his name is Old Man Middleburg, and he knows too much.
Larry Manor is revealed in "Trading Faces" to be Old Man Middleburg's ancestral mansion. He was forced to sell it to Larry because of financial difficulties. In "At the End of the Worlds", Larry gives it back to him as a farewell gift.