Guarded by the Abyss

When Sloane was six, she watched her mom get shot by a mob boss. Her mom hid her under the bed and saved her life. Twelve years later, Sloane's locked up by her four brothers for "protection." She breaks free, digs into her mom's murder, and finds out the mob boss never stopped hunting her—her mom left behind evidence that could destroy his whole empire. Sloane uses it as bait, teams up with her brothers and bodyguard Kai, and takes them all down. Meanwhile, she and Kai fall for each other in secret, and he has her back when it counts most.