Third Responder
From Gomerpedia
A third responder is the third person who responds to an emergency. The third responder is the worst.
Dialogue Between a First, Second, and Third Responder
FIRST RESPONDER: Well, it's about f**king time you got here.
THIRD RESPONDER: Whatever...
SECOND RESPONDER: In all the years we've been dealing with emergencies, you're never the first or second to respond!
FIRST RESPONDER: Yeah, what's that about?
THIRD RESPONDER: Geez, you guys are such gunners... I'm gonna go grab something to eat.