Hiro started out as a young spunky pup, play fighting with his sibling Osaka almost every day. Until he was captured by a self proclaimed 'evil mastermind' named Pluto, and had that spunk beaten from him. It wasn't until he became a young adult that his brother was able to find and rescue him, and had to since help him recover both mentally and physically. Hiroshima is a quiet shell of what he used to be, having aggressive outbursts at times, but somewhere inside a puppy still lurks wanting to explore the world.