His Favorite by Eve Vaughn

Tamryn Smith is a survivor. She knows the mean streets like the back of her hand. She has what it takes to get out of a tough situation. She’s even willing to kill to stay alive. But when she’s faced with a new threat in the form of a tall, dark and dangerous Irish bad boy, she may have finally bitten off more than she could chew.
Seamus Haggerty was hardened by the life he was born into. Having faced dangerous enemies for most of his existence, he never thought his biggest challenge would be the very thing he swore off: love. But when he lays eyes on Tamryn, he has to have her. And he will.
But what happens when one taste becomes an obsession?