Promises stronger than darkness - Charlie Jane Anders

THEY'RE THE GALAXY'S MOST WANTED - AND OUR ONLY HOPE. Elza became a space princess, and is now on the run. Rachael followed her best friend Tina on the adventure of a lifetime - but now she's the only one keeping her friends together, on their desperate quest to save everyone from an ancient curse. They have one clue that has them enlisting the aid of Captain Thaoh Argentian, the woman who stole Tina's body. With only a ragtag band of misfits, crewmates, earthlings, friends, lovers (and one annoying frenemy), the Unstoppable Crew are up against the universe--and they may have to cross a line they vowed never to cross.