Joji Tomioka

Tomioka is cruel, sexually predatory and threatening. He shows no remorse toward Ayaka and continues making sexual remarks toward her even after they are both transported into Gantz.

His confidence increases once he possesses Gantz weaponry. When Ayaka attempts to confront him, Tomioka uses the supposed superiority of his weapon to intimidate her into hesitating.

He remains closely associated with the other men responsible for the assault rather than integrating with the established Tokyo team.

Tomioka has no established supernatural abilities or specialized combat training.

As a Gantz participant, he gains access to the enhanced suit and advanced firearms supplied by the black sphere. He survives the Ring Alien mission, demonstrating at least enough competence to avoid being eliminated during his first hunt.

His subsequent appearances do not establish him as a particularly skilled hunter compared with the experienced members of the Tokyo team.

Tomioka arrives shortly before the Ring Alien mission as part of the group surrounding Ayaka. After the mission, Ayaka tells Reika Shimohira what happened to her and attempts to contact the police.

During the mission targeting Tae Kojima, Ayaka confronts Tomioka with a Gantz weapon. He responds by threatening her and claiming his own weapon will kill her first.

Tomioka later remains with several of the other attackers during the Oni Alien mission. The group encounters one of the Oni leaders and is incinerated during the confrontation.

Ayaka Uranaka is Tomioka's victim and openly wants revenge against him after they enter Gantz. Tomioka continues threatening Ayaka Uranaka rather than showing remorse.

Naoichi Mikawa, Ryotaro Haga and Kaoru Iwamoto are among the other men associated with Tomioka after their arrival in the Tokyo room.

Reika Shimohira protects Ayaka while she attempts to contact the police after the Ring Alien mission.