Wiktionary
gloomy gus
alt. (context informal English) A person with a sullen, unhappy appearance or demeanor; a person with a pessimistic outlook. n. (context informal English) A person with a sullen, unhappy appearance or demeanor; a person with a pessimistic outlook.
WordNet
gloomy Gus
n. someone with a habitually sullen or gloomy expression [syn: sourpuss, picklepuss, pouter]
Usage examples of "gloomy gus".
I would have called him a pessimist, only I couldn't think of the word, and while I was trying to hit on something other than 'Gloomy Gus', which would scarcely have been a fitting way to address one of his dignity, Florence came in through the french window and he of course shimmered off.
He had no time to listen to pessimistic warnings from any Gloomy Gus of a Subconscious Self.