Crash And Burn by Cynthia Sax
Crash was manufactured to be one of the best warriors in the universe. The cyborg has spent many human lifespans fighting the enemy. But, unlike his battle-loving brethren, he doesn’t enjoy killing. When he escapes the Humanoid Alliance, he vows to never end another life.
Then he meets Safyre, an infuriating human female, and he considers breaking his vow.
Safyre will do anything to save her friend, the being she loves like a sister. She’ll ravish a huge hunky cyborg, kiss his best friend, and invoke scorching hot desires the male never realized he could feel. Dark soulful eyes, a quick wit, and a tempestuous passion won’t divert her from her mission.
Love, and a planet-destroying weapon, however, might stop her permanently.