Disposable Heroines

In a certain kind of spy fiction, the titular hero is a constant of the series whereas there is a different heroine in every episode so what happens to heroines between episodes? In his Dominic Flandry series, Poul Anderson usually tells us:

Flandry and Persis part;

Djana leaves;

Kathryn stays with her husband;

etc.

 

James Bond does not dispose of as many as we might think. Of twelve novels, only four leave the fate of the heroine unresolved.

 

In Casino Royale, Vesper Lynd is a double agent and commits suicide whereas, in A Circus Of Hells, Djana refuses to become a treble agent, curses Flandry and leaves. Thus, I found an oblique symmetry between the conclusions of these two novels.