Hiroya Oku is an artist who created Gantz, Zero-One, and HEN manga series that were published in Young Jump magazine. His work often includes violent and gory scenes as well as sexual content. In 1988, he won the second prize of the Youth Manga Awards under the penname Yahiro Kuon. Oku also designed a character for Namco Bandai's Soulcalibur IV video game named Shura.