Crescent

Her motto is "Life is Death! Death is Life!" Can a warrior trained from birth to kill be trusted? Crescent is a gene-tweaked mercenary programmed to fight to the death. When she's captured by Crater Trueblood, a miner turned soldier, she can't understand his kindness. Maria Medaris, once Crater's girlfriend, has become a ruthless competitor in business and in life. When a murderous band of assassins attack, Crescent, Crater, and Maria escape to a lunar ghost town called Endless Dust. To survive they must do more than navigate the desolate moonscape and battle a persistent band of killers. They must decide what—and who—is truly worth fighting for.