Fight for Her by Sara Hazel

Drake Fierro has had to fight all his life–growing up on the streets, in the war, and now in the realm of business. Drake has won every fight he’s been in. But now his past threatens to haunt him in darker ways than he has ever been prepared for. And a new complication has arisen —
Emilia Vera — the very beautiful daughter of a very dangerous man. Emilia’s father whispers to the denizens of Chicago’s underground and things happen. Bad things.
The curvy brunette leaves Drake lying awake at night. He can’t stop thinking about her. He won’t stop thinking about her.
The one thing Drake knows is that Emilia will be his somehow. Even if he has to battle his way through the entire Chicago underworld fight circuit and the mob itself in order to have her.