I'd like to apologize in advance if I don't make sense. I'm not a native English speaker.
Anyway, here's the background: Back home, it is common that your friends ask you for a treat for every little thing, just another reason to celebrate. By treat, I mean treating someone to food and drink/hosting a (dinner) party just for a person or two. However, there are a few people who ONLY ASK for a treat but never really accept it. And that is not the end of the story, they then complain that we never treat them.
I know its not a very common scenario, but I'd like to know if there's a word for such people or such a behavior?
For example, I'd like to use it in such a sentence:
Just invite him. He'll not join us anyway, he is a _________.