I was watching a movie and noticed this sentence used as a response from a person introducing himself/herself. This is quite odd for me as a non-native speaker of the language.
Example:
Setting: In a bar
Scenario: Person A is friends with Person B. Person A introduces Person C to Person B.
Person C: Hi, I'm Jane.
Person B: I know you are. * smiles *
As a receiver of the response (Person C), what would my reaction be? Or how do I take this kind of response?
As Person B, what are my intentions for saying this response?