After reading Benjy's section, I was surprised to find Quentin's even more incoherent and hard to follow. While Benjy omitted question marks, Quentin often omits any punctuation and capitalization. His mind jumps to the past much more than Benjy's. It's interesting how similar the voices of these two opposite characters are. I think Faulkner is trying to say that no one can escape memories of the past.

About the young Italian girl.. I think Quentin helps her because he feels he failed at helping his own sister. He feels he should have protected Caddy better and wishes she had not been forced to marry Herbert Head. He calls the Italian girl "sister" several times, and is very distressed that she doesn't have a home.