[Opinions] Re: Huckleberry
"Wow, stereotype much? I find this highly offensive, fyi."
I think that might be her point. The circumstances and rough outline of Huck seem like a stereotype. Of course, Mark Twain somewhat takes this stereotype and flips it by having a character that circumstantially embodies all kinds of negative stereotypes about so-called 'white-trash' and then makes him the relatable hero of his own story and a decent person at heart.
Note: I have never personally heard Huckleberry Finn used as slang word. It may be worth noting that some people may consider it one or at least heavily associate it with the character and his circumstances/backstory.