Broken Ties by M. Malone, Nana Malone

I was the hero once, until I was betrayed.

Now I’m something else. I am the shadow that haunts the night. I am a hunter, a protector. I am Jonas Castillo.
For years I’ve existed on the edge of the dark, protecting innocents who can’t protect themselves. Until… her. Jessica “JJ” Jones. The bane of my existence. A bright light in the dark. The crack in my armor. A loud, argumentative beautiful crack in my armor.
But first, there’s a more immediate concern. JJ is running scared. And to protect her I might have to break the vow I made years ago.