Echo

For eight years, Echo murdered her way across the galaxy in the service of the Emperor. She had lost count of the number of bodies she left behind; they didn't haunt her sleep any more. York was a hero who walked away at the end of the war, sickened by the pointless casualties and personal loss: something that haunts him still. Their paths crossed once before, the night she killed for the first time. Eight years on, York's ship is hired by the Empire. Echo is his only passenger. He's surrounded by his own killers, who all think Echo is there to murder him. They may be right.