Gabriel Blackstone's world is divided quite clearly into castes: everyone knows their place and abides by it. As an inventor in the merchant caste, his life is predictable in its routine until the night his best friends and assistants, Caleb and Andrew, purchase the time—and body—of a companion for his birthday. As an activist in the Caste Equality movement, everything Gabriel believes in tells him to refuse the gift, but then he meets Lucio. The beautiful and alluring companion is far more than the vapid courtesan he'd expected, and he can't get the man out of his mind.