Great Movie, but could have done with some editing and some changes.
SPOILERS.
The lesbian character was not needed, nothing happened between her and Norah because Norah was not gay!
They didn't even become friends, so that scenario was completely useless, the movie could have used that storyline but made that character an Asexual male instead who becomes good friends with Norah.
The sex scene at the party was not needed, we already know that Norah is messed up way before that scene. However, it was obvious that the Filmmakers wanted to make it clear to the audience that Norah was straight, hence her sleeping with a man.
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