You read it veryyy wrong lol
She was acting as a wife to some old man and gathering intel behind his back.
MC was there on a secret lookout and she came out to talk to him and dinner with him, then she told him she is in love and has caught feeling for the target and tells MC someday it might happen to you too in a sad way because she knows it is not possible for her to stay with the target and just wanted mc to sympathise with her situation and not do something rash like telling everyone on the team that she has become emotionally involved

DAMN HIS WIFE WAS AN UNDERCOVER COP AND HIS COLLEAGUE AND THEY HUNG OUT AND SHE CALLED HIM SUNBAE AND THEY WERE IN LOVE (?) AND SHE WAS LOOKING FORWARD TO ENDING THE ASSIGNMENT (?) AND SHE WAS SO PRETTY HELLO WHAT???? I NEED THEM TO COME BACK TO LIFE ASAP PLEASE LIKE THEY LOOK SO COOL!!!