Vindiktor is a brother of Natasha Romanoff. When they were children, their house caught fire. Their mother threw Natasha out the window, saving her, but the rest of the family presumably died in the fire.
Years later, when Natasha returned to Russia, she met her brother. He blamed her that she left her family and her brothers, who survived the fire. He tried to kill Natasha, but was killed by her in return.