I don't know exactly. It could be comics from indie publishers or mainstream ones. Maybe he has a diverse collection covering various themes and characters.
Yes, there are. Some movies draw inspiration from various sources but not directly from comic books. For example, 'The Truman Show' has elements of a fantastical world but isn't based on a comic.
Well, a blank comic book isn't really an actual comic book in the usual sense. It doesn't have pre-drawn characters, plot, or dialogue. It's more like a canvas waiting for your imagination to fill it up.