Stargun Messenger

Astra Idari knows she's human.
Others see an android with a bad memory stitched together by her ship's snarky AI. She only wants to live as she is and escape the monotony of tracking down thieves of ultra-rare starship fuel.
When a job leads her to Gen Emera, Idari meets the girl of her dreams and the last living star. There's just one problem. Idari discovers starship fuel is found only in the blood of living stars.
Idari has one option: turn Emera over to her shadowy employers. A Stargun Messenger protects the fuel trade; without it, intergalactic civilization collapses. But Emera illuminates something in Idari, and she chooses to help Emera escape certain death. In an instant, Idari goes from hunter to hunted.
She races across the galaxy and against time from bounty hunters, pirates, living shadows, and her own fears. Emera's life depends on Idari's humanity if Idari is finally ready to risk it.