Yuugo Kamishiro

Yuugo Kamishiro (神代 勇吾) is Yuuko's older brother. Pre-release materials referred to him as mysterious boy (謎の少年).

Appearance
Yuugo is a teenage with black hair and eyes. He wears a white shirt with long sleeves and a ruffed hood, black pants, and white shoes with gray soles. As the "Ghost of the White Boy", Yuugo's hair and pants become white, an his eyes become gray.

Digimon Story: Cyber Sleuth
There's a rumor among hackers that say those who've encountered "Ghost of the White Boy" in Cyberspace EDEN have their data erased and are no longer able to access EDEN.

When Nokia Shiramine and Arata Sanada meet in Kowloon, Arata leaves to search for the ghost, but fails to find him. When Aiba tries to find another exit from Kowloon, they meet the ghost, who gives the teen a "fragment of memory". After Aiba wakes up, they mistake Yuugo for the ghost. The ghost watches Aiba and Nokia as they arrive near the Logout Zone.

Later, when Aiba and Arata enter a digitalized subway in Shinjuku, Aiba sees the boy again, but he disappears before Arata can see him. Akemi Suedou claims the boy is an omen, and that his presence indicates the Eaters' presence.

When Ryouta gets a part-time job to investigate suernatural occurrances, he is tasked by his employer to take a picture of the ghost. In Kowloon, Aiba sees the boy behind Ryouta, but he leaves before Ryouta is able to see him. Ryouta then tries to chase the ghost.

Digimon Story: Cyber Sleuth - Hacker's Memory
Erika Mishima comes up with a plan to cure Chitose Imai of his Eden Syndrome and manages to hack an Eater, after she and Keisuke Amasawa searched for one using tools provided by Akemi Suedou. Erika manages to use the data she found to access the Eater World, in which her, Keisuke and Ankylomon come across Yuugo Kamishiro. After explaining the situation to Yuugo, he allows them to locate Chitose's memory data. They then upload the data back into Chitose's mind, causing him to be the only person to ever recover from Eden Syndrome.

Digital body
After Yuugo was striken with the EDEN Syndrome, his mind became a digital body, which is similar but different from Aiba's half-digital body.