Hi, There is a guy, who is wearing his sunglasses on the top of his head. The girl I am hitting on, made a compliment to him and he told me that. Thats how it went:
SHE: Give me a favour.
GUY: Yes
SHE: Put your sunglasses on please
(he puts them down for her)
SHE: Oh, my God, you look so good
So, now, I want to let her know that I know about her giving him a compliment. This way I intent to highlight to her that the guy is "kiss and tell" But I am not sure how to wrap it nicely with fun, same time telling her that she is allowed to make compliments to me only

(we all see each other every day at work)
Any suggestions please and thank you.