The Clerk is a female character in City Folk that sells tickets at The Marquee. She is very business-like and never reveals anything about her personal life. Nobody knows what she looks like, because she is always behind the counter, trying to sell tickets to shows of Dr. Shrunk and Master Frillard. The tickets cost 800 Bells. The Clerk isn't a human because she speaks Animalese whilst the player speaks Bebebese. She always says the same thing. She never includes hints or mentions anything different from selling tickets.
Warning: Theory starts here.
The Clerk is the Emcee
Though this has not been proven, the Clerk may be the Emcee. This theory is supported due to the similar roles of their jobs and their identical voices.