Hajime Muroto

Muroto is a main antagonist in the final stage of Gantz. He is a central character in the Kurono Alien arc and does not make an appearance in the manga. He is sixteen years old. Muroto is almost always seen alongside partner-in-crime Kajimura and is known for his sadistic and violent acts. Before the Gantz missions, he died as consequence of crime and was shot to death shortly after Kajimura. He blames society for what he is today and also cites his parents' abuse as a contributing factor to his mania. Although he ruthlessly takes lives and displays great enjoyment in doing so, he claims that he does a lot of things out of fear of being the one to get hurt first.

For most of the Kurono Alien mission he relies on his "acting skills" to mislead the group, making himself out to be an innocent teenager being dragged along by bad influence Kajimura in a life of crime that he wants no part of. Muroto pretends to by shy and fragile but at the same time suggests an attack on Kurono whenever he can.