Arrogant.

I had a lunch and dinner with Neil Gaiman and Amanda Palmer a year ago (my friend officiated their wedding), and while Neil Gaiman was super-nice, polite and extremely kind person with absolutely no celebrity feel and treated everyone the same, Amanda demanded constant attention, behaved like a spoiled celebrity brat, commanded people to change seats during the whole lunch (ignoring they were having conversation on their own) so that she could be the centre of attention, and picked arguments just to dramatically express her opinions. Arrogant and full of herself. Ugh, nice to get it off my chest :)