After spending the first seventeen years of her life isolated against her will, Serenity finally reaches the age to start mating. In a world where powerful magic can only be passed down through the Y chromosome, males and females are separated at birth in order to hone the powers of males, and keep the endangered female population safe. Serenity gets by day to day after her dreams of leaving her sector to dance were crushed years ago. It is only when she finds two mates at the yearly Assigning, that she learns what type of world she actually lives in, and what she is truly capable of.