Watch the damn scene. She is trying to brush him off. She wants to leave, and he is not letting her. She is politely saying no, and he is politely forcing her to stay. Even if it is due to social pressure, let her fucking leave.

“Well maybe just a half a drink more” is said when he has just snatched the coat off her back and is still holding it. Her face is a picture of resignation, not coy flirtation. She then asks “say, what’s in this drink” and puts it down with a scowl on her face.

This is flirtatious by the standards of a Sean Connery movie.