Marrying the Underboss by Elisa Leigh

Jennifer is the only daughter of Lorenzo Perrelli, the Crime Boss of New Jersey. She’s been living a peaceful and normal life for years, but things suddenly take a dangerous turn when she’s thrust into the perilous world she’s always tried to avoid.

Kane Rossi, the Underboss of the Perrelli Crime Family. A man capable of violence and ruthlessness keeps himself at a distance from everyone. When he learns that Jennifer is in trouble, he’s the only one who can protect her.
Kane will go to the ends of the earth to make Jennifer his own, even if it means defying his loyalty to The Boss.

Meanwhile, Jennifer is determined to live a life outside the one her father rules.