Joichiro Nishi

According to some half Japanese fansite his name is Johichiro and in the official Dark Horse translation of the manga he originally names himself Ichiro Nishijo. But when the first mission ends he is called Mr. Nishi by Gantz. Afterwards he is mostly known as simply Nishi.Since he probably was lying when he introduced himself and most people know him as Joichiro Nishi. This is the name we will be using for him.