This is a demonstration of an author's "idiocy".
ACOURSE is a misspelling and also a misrepresentation of actual English words.
The phrase being referred to is OF COURSE.
It means YES.
But when some people speak, they slur their speech, and this is what the author is showing.
The author thinks there is some benefit in showing that the character speaking slurs his speech.
The author could communicate objectively, and simply write OF COURSE to show what his character is saying.
Still, look at the confusion the author creates when some Non-Native English Speaker tries to read his book. It is in my opinion, a demonstration of a kind of literary idiocy. It is just as easy to write OF COURSE, which means simply, YES.
I don't find coy writing like that on the part of authors, any benefit at all.
So now you know.