Mike "Temp" Ferret got his nickname because for the longest time he was just floating between temp assignment to temp assignment, often times getting canned rather than hired on for anything lasting for longer than a week; often times he would end up losing the job the same day he got the job. He's generally a bright ferret (despite the fact that he's still struggling with a smoking habit he picked up early in life to "take the edge off") who just keeps getting the short end of the stick... time and time and time and time again.

Life doesn't really appreciate Mike's diligence in return, it seems.

(Incidentally, the reason that Temp's "real name" is Mike has everything to do with Mystery Science Theater 3000 and the season after Joel left the show:

o/` They hired a temp by the name of Mike

Just a regular Joe they didn't like o/`)

(Also incidentally Mike's a base coward, both despite the fact that for a decent stretch of time on the Funday Pawpet Show he was actually murdered live on screen just to return the following week and he plays video games in the Silent Hill series, a game series renown for it's point-blank use of psychological horror. No, Mike's not even sure why he loves the series. Might have something to do with the person that controls his puppet...)