Almost all the funny lines were from Aldous Snow. Like this one, where he's wearing a Hawaiian shirt that's a gift from his girlfriend. He hates the shirt.
Aldous Snow: [after spilling red wine on his shirt] Oh God, take my eyes, but not the shirt!
Or responding to one of his fans:
Matthew: I have a question for you real quick. What did you think of my demo? Did you get it?
Aldous Snow: I was gonna listen to that, but then, um, I just carried on living my life.
Or his description of his vacation with his girlfriend:
Aldous Snow: I don't know how you put up with her. It's like Hitler. Maybe that's going too far. No, it's not -- it's like a holiday with Hitler.
I wish more people were this hilarious in real-life. However, the reason the character is so funny is largely due to his cruelty. It wouldn't be good for more people to go around dashing youngsters' dreams and mocking the fashion tastes of their loved ones.
But it's so funny!