Books
With men he can be rational and unaffected, but when he has ladies to please, every feature works.
— Jane Austen ‧ Emma

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
According to the speaker, this man is sensible and natural when talking with other men. Once he needs to charm women, though, his whole face goes to work. The remark is a dry, gently mocking observation about calculated charm and the difference between his two manners.
Context reviewed