intro.

With the cities growing from clouds and the railways hanging over oceans, humanity has reached its calmest. But each fertile woman and each fertile man must be married by age twenty-five in order to guarantee the continuation of the human race. As freeing as this airy world is, perhaps anyone can feel trapped in a birdcage when wedded to a stranger. And maybe keeping friends close will be harder than one would imagine, especially when grave danger lurks over the horizon.