Highschool Gun High Gun

Tyler Calvin is a child with a dark past, having lost both parents in a plane crash as well as his memories at the age of five. Tyler was raised to be a child assassin until the day when he was whisked away by the Advanced Counterterrorist Division where after hitting the age of 17 he regains some of his memories. Now having returned to live with his older sister and aunt in Reinfield city, San Francisco Tyler dreams of living the peaceful life yet coincidentally he is thrown into an extinction level threat that he must face together with his friends and allies that are of a different world other than the criminal underworld. What crazy world awaits the young teen?