Have you even wanted something so bad you could taste it?
That the kind of hunger I'm talking about - wanting something.
(Now I'm trying to think of something not food relative.....)
All right you want a giant shark plush!
What all are you going to do to get this giant man eating plush?
Are you going to the store?
Search the Internet?
What if someone tell you (like your parents, your roommate or your spouse) that there is not way they're having that in their living room!
Creating an antagonist or any character really is knowing what he or she wants and at what length they are willing to go to get it and what or who stand in their way.
What is your character hungry for? Is a very important question for an author. One I notice I have a problem with while writing.