Inamori is a blond, 20 year old guy who showed up in the Gantz room before the Onion Alien mission. When Yamada Masashi tried to get everyone in the room to tell their names, ages, what they did when they were alive and how they died, he refused to do so. Instead, he kept asking for cigarettes. Kurono thought that Inamori had a girly face.
During the mission Inamori was careless with the weapons. When he first picked up an X-Gun he pulled a single trigger while pointing it at Masashi, avoiding killing him only by chance. He also pointed the rifle at Hatanaka Hiroshi, making him angry, and demolished a wall when he missed shooting the Onion Alien. He later killed Hatanaka by accidentally shooting him when the big onion alien used his body as a shield to block the X-rifle. Inamori was killed by the big onion alien during the first mission.