The Black Dragon's heir

After almost dying at the hands of a creature out of a fairy tale, Locke awakens a power hidden in his blood, drawn into a secret war that puts the entire human race at risk, Locke finds himself with no options but to fight, even with their own humanity on the line. Using the system left by his father to become stronger, will Locke be able to protect those he loves or will he become an even bigger monster than those he fights?