So the bar owner asks the bartender...

[sageratslayer]

... "Hey! Are you sleeping with the waitress???"

Bartender says "No!"

Bar Owner says "Good! Then you fire her!"

[WV1951]

Or

Bar owner to bartender. " I've got some good news and bad news.

Bartender " What's the good news?"

Bar owner " I've been sleeping with the waitress"

Bartender "What could possibly be the bad news"

Bar owner "You have to fire her"