There are a few libraries. do you use the online or the downloadable version of Quest?
(Hello. I'm substituting for jmne, as she appears to be away at the moment.)
Sadly, you can't use libraries online.
If you can't install the Windows desktop version of Quest, the documentation is pretty good:
http://docs.textadventures.co.uk/quest/#handling-characters-npcs
I'd also recommend going through the tutorial first if this is your first Quest game:
http://docs.textadventures.co.uk/quest/tutorial/index.html