Broken Trust by Nana Malone

I’m what some people call the bogeyman. Most people have the good sense to be afraid of me. Unfortunately, my best friend’s little sister is NOT most people.
She’s not afraid of me at all. But she should be. She doesn’t know the secrets I’m hiding.
Look, Lucia Demarco is a handful. She’s stubborn, gorgeous, a magnet for trouble, and sets my blood on fire.
Ignore that last part. I can’t have her. I promised my best friend on his deathbed that I’d always take care of her. And I have…never you mind about the thoughts that plague me at night
The point is, she’s been poking her head where it doesn’t belong and now some idiots are about to find out why they call me the reaper.
I hear former hitmen make the best bodyguards. True story!
I’ll keep my word and keep Lucia safe. And I absolutely refuse to give in to her sunny smile or sharp wit.
I can be strong. Or will I risk just one taste?

A standalone romantic suspense with a morally gray anti-hero willing to do anything for the woman he has pledged his life to protect. Previously called the Shameless series, Broken Trust is a completely revised and expanded edition with no cliffhanger and three epilogues. CW available on the author’s website.