The story starts with the MC kidnapped and finger cut. Later, after the kidnapper is caught, the father/grandfather of kidnapper offers the kid the wealth sourced from his now incarcerated son/grandson. They then bond and fly around on private jets wrecking bad guys.
(I don't recognize the story, but I'm confused by the plot: usually the parents of the kidnapped kid are rich, and the kidnapper is poor, which is the opposite of how you describe it? How did the plot in the story work?)
The MC comes out of the kidnapping with some trauma since his entire family was also killed by the guy. He was a serial killer from a rich family, and after his crimes are exposed his family pays off all the victims' families. Since he was the only victim that survived he was offered all the wealth from the rich serial killer, which was put in a trust. He is then trained by the rich father/grandfather's security guy ( a former SEAL called Sean I think) and they then go around destroying gangs and global syndicates. I just can't recall the title.
kid grows up to become a marine in human Phoenix not a vigilante.
in a story matching op description a young boy is the sole surviving member of his family that was murdered by a serial killer.i think the boys name started with a d,like Derek or something
