Differences Between Book and TV Series:
In the book series, she has a shaved head and wears all black attire; in the TV series she has curly hair and has a very bad fashion sense.
In the book series, Vanessa loses her virginity to a guy who works at the club her sister Ruby plays at; they also dated briefly. In the TV series she is still a virgin.
In the book series, she wasn't long time best friends with Dan, since in the books she just moved to NYC from Vermont when she was 15, he is disinterested in her in the first book, because he's always smitten with Serena van der Woodsen.
In the book series, Vanessa's sister is in a relationship with a man. In the TV series, Vanessa mentions that her sister is in a lesbian punk band.
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