Choi was born in Seoul, Korea and came to the U.S. when he was two years old. He formed a boyhood friendship with future comic book collaborator Jim Lee, and began creating comics together when they were both in the sixth grade. Choi and Lee's 1986 comic Wild Boys landed Lee his first job at Marvel Comics.[1]
Choi studied entertainment law after high school, but changed careers after graduation. While making plans to attend graduate school to study screenwriting, Lee contacted Choi with an offer to work at Homage Studios, which later became Wildstorm Productions.[1]