My Repairman Daddy is the Star Warmaster

Thirteen years after vanishing into hiding, Supreme Warmaster Eric lives as an unassuming mechanic on a junk planet. But when his runaway alien bride, Lyra, returns beaten and hunted with their twin toddlers, the sleeping dragon awakens. Corrupt lords mistake him for scrap meat, unaware that one snap of his fingers can raze a fleet. "Touch my wife or daughters, and I will burn this entire galaxy to ash."