Merchants of Knowledge and Magic by Erika McCorkle
On one of the many planes of the Pentagonal Dominion, priestess Calinthe trades in information, collecting valuable secrets for her demonic employer. Calinthe has a secret of her own: she's intersex, making her a target for the matriarchal slavers of the Ophidian Plane whose territory she must cross in her search for hidden knowledge. But thanks to her friend Zakuro's illusions, Calinthe presents as a woman—a comfortable, if furtive, existence in a world determined to bring her to heel. But when, instead of a mere secret, the priestess uncovers an incalculably powerful artifact, Calinthe finds herself in a high-stakes negotiation with the same matriarchs who sought to enslave her. On the table: Calinthe's discovery, a charm powerful enough to transform a mortal into a god… against a secret so deadly it could quell all life on every plane of the dominion. If Calinthe plays her cards perfectly, she and Zakuro could escape Ophidia wealthier than either of them ever dreamed possible. But if she plays them wrong… …she'll learn slavery in her pursuers' hands is a fate far worse than death.