Saturn's Children (Freyaverse #1)

Sometime in the twenty-third century, humanity went extinct leaving only androids behind. Freya Nakamichi 47 is a femmebot, one of the last of her kind still functioning. With no humans left to pay for the pleasures she provides, she agrees to transport a mysterious package from Mercury to Mars. Unfortunately for Freya, she has just made herself a moving target for some very powerful, very determined humanoids who will stop at nothing to possess the contents of the package.