Kazou was born on the planet Yosuzume in 2826 to a poor family, and showed an interest in alien artefacts and 'those who came before' from a young age. He managed to save up enough money to seek passage to the planet Raijin in 2851, the capital of alien artefacts in the known universe. He met Jack in 2879 who was then a budding privateer, who would bring Tsutomo artefacts he found from his travels for a large cut of the profits, they became fast friends.