Famous Koala and Prostitute joke!

Let me tell a joke that I once heard during bus trip to Stockholm. It was a joke told by Italian guy with a special Italian accent. The joke is like that:

A koala enters a popular tavern in Melbourne and sits down at the bar. It isn't long after he's sipping on a martini when he's approached by a prostitute. She sits down next to him and asks him if he'd like to have sex with her in the back room. Being a typical male, the koala complies and follows the slut to the back room. He finishes and then returns to the bar. He grabs his coat and heads for the door.
Before he is to leave her the hooker had asks him where he is going and when he intended on paying her for the sex. He was surprised, so she tells him to look up the word "prostitute" in the dictionary.
He reads "prostitute - one who receives money for sex"
The koala then hands the dictionary to the prostitute in and tells her to look up "koala." She reads "koala - a member of the marsupial family who eats bush and leaves."

Thanks to Italian guy for made me laugh!