What's with the claim that Anna pulled a knife on Nobuko?
I bet that after 2 years, you don't care if someone answers the question; heck I wouldn't. Or, maybe you found the answer, but recently I have decided to read the novel.
That was just part of the film. A box cutter is a type of knife, so the dub/sub was similar, but there was no talk about a knife in the book. Maybe it's just something someone added in the film to make her look meaner than Anna was supposed to be.
I'm not a fan of the film, but I will see how the book ends up. I'm about 1/3 finished right now, but the movie follows it alright; for now.