Detective Sarah Vance is the city's toughest cop, hunting the vigilante 'Ronin.' She comes home to Noah, her clumsy, soft-hearted librarian husband, unaware he is the very assassin she’s hunting—and that he uses her police files to target the corrupt oligarchs she can't legally touch.

Five years in a foreign prison. He missed his daughter's first steps, her first words, her first bruises. Now he's back. And the people responsible are about to find out — they should never have touched his family.

"Sign the contract, Aven. Or watch them turn off her oxygen."Five years ago, elite prodigy Aven Cross fled into the shadows, carrying a secret that could destroy her life.Now, she is breaking bones in illegal underground cages, desperately fighting to raise fifty thousand dollars before sunrise to keep her four-year-old daughter alive in the ICU.But the man standing outside the cage isn't a regular promoter. It's Kallan Vex—ruthless combat mogul, undefeated former champion, and the ex-coach whose bed she fled before dawn.When Kallan spots the pink hospital wristband beneath her bloodstained tape, he traps her with an ironclad deal: sign an exclusive four-year contract, move into his tower, and surrender to his rules—or watch her child fade away.He thinks he just bought his next world champion. She knows she just walked into the lion's den with his secret heir.