Joji first appears in episode 3 in a cafe, discussing with Kei about their upcoming project/book on the Cosmos Chronicle. When Kei actted stange, Joji asked him what happened and Kei told him he is just meeting with somebody he does not like. Joji is the editor of Kei various novels of the Cosmos Chronicle.
In episode 7, when Kei conducted a concert about his new story, he is present at the concert as well. He also witnessed Kei summoned a Galactron and helding his audience as hostage unless Ultraman Zero sacrifice himself to save them. He is later seen in the media along with Kei when the Kei is being interviewed by the reporters on how he felt about what happened.
Sometime before episode 11, Joji started working with the AIB as an undercover while still being Kei's editor. Joji was seen writing down notes on what Kei says, which is about their upcoming project/book. When his secret of being undercover of the AIB is uneviled, an Alien Neril tries to take him to safety but Kei knocked down the alien, he told Joji that he is thankful for his hardwork and he is that the project have to be cancelled.
In epsiode 18, after Ultraman Belial's defeat, the news revealed that Joji is now dead, much to Laiha Toba and Riku Asakura's shock as they watches the news. Kei is now a refuge as police is now searching for him for being the suspected murderer of Joji.
- Joji's name is a reference to sci-fi writer George O. Smith