His Iron Vow. The Iron Covenant, #1

Mara Collins never meant to expose a criminal empire. She only wanted answers. When her powerful employer's secrets turn lethal, Mara runs-with evidence she barely understands and enemies who won't hesitate to silence her. What she doesn't expect is the Iron Covenant: a shadow organization that operates where the law fails, bound by a code that forbids the one crime no one else seems willing to stop.
Luca is Covenant muscle-controlled, dangerous, and sworn to a vow that doesn't bend. Protecting Mara should be just another operation. Instead, she challenges everything he's built his life around. She asks the questions no one else dares. She refuses to be owned, traded, or erased. And when the Covenant is betrayed from within, Mara proves she's not a liability-but a force. As the hunt for traffickers escalates and suspicion turns inward, Luca must choose between the organization that saved him and the woman who has claimed his future.
Because the Iron Covenant doesn't promise safety or survival. It promises effort. Relentless. Uncompromising. And when Luca gives his word, it doesn't break.