Chang Bowen is one of the three friends who participate in Kazuya's Salvation Game. Like Mario, he came to Japan in order to seek money to get out of poverty. He was originally from a poor rural village in China and the second son to a poor family. Because of China's single child policy, he was sent into a life of hard manual labor at a very young age. Chang did his best trying to learn Japanese with the materials he bought from what little money he had, aiming to purchase a family register and migrate to Japan to feed his family.

(Source: Kaiji Wiki)