Antonio Lopez, also known by his hero name Rock Bison, is a character from the anime series 'Tiger & Bunny.' As one of the veteran heroes in the show, he works for the company 'Helperides Finance' and is known for his bull-themed costume and powerful defensive abilities. Despite his strong exterior, Antonio is a gentle and caring person, often providing support and advice to his fellow heroes. He shares a close friendship with Kotetsu T. Kaburagi, the protagonist, and his role in the series highlights themes of camaraderie and perseverance.