Embers Between Us

OC story but it's also an alternate universe where Izuku has a twin brother who has a quirk. Pyrokinesis.

In this world, Izuku Midoriya had a twin brother, Paira Midoriya. Paira, unlike Izuku, had developed his quirk. But because of the quirk he had gained, he was taken by their dad in the divorce. They had moved to America where their father had trained him in the most torturous way, raising him into a weapon. Once his training was complete by age 14, he was sent back to Japan and given to All For One to be his weapon. But he escaped at age 15 during the USJ attack when Shigaraki had left and was found by teachers, hiding in one of the disaster zones, the next day. He was taken to Nezu instead of the police where he was questioned by the Principal and then given a choice to either join the hero course or face the police. He chose the course. Izuku and Paira were reunited the week after the incident.. but not in the joyous way one would hope. Paira was serious and deadpan throughout the whole reunion, including with their mother. Will he be able to break free from the weapon mindset tortured into him and become a normal teenager? Or will he forever be a mindless assassin in the disguise of a hero?