Unleashed — Sigmund Brouwer

Jace has it all -- money, cars and status. What he doesn't have is a happy home life. Forced to protect his brother from an abusive father and a neglectful mother, Jace lives a double life on the wrong side of the tracks, learning to box and trying to survive on his own merits while plotting to expose his father as the monster he is. Working reluctantly with two girls who have their own thoughts of vengeance, Jace finds that he is not as alone as he thought and that there are people he can trust.
   
Part of RETRIBUTION -- a high-interest trilogy that can be read in any order.