He'll be back. Anyway Izumi and Kurono has some business to finish so Izumi might kill him and he'll be back again on the next Gantz mission. Kurono will be a coward and selfish cry baby during the mission. A lot of his companion will die and he wont care. When Kurono gets between life and death he'll have a long ass flashback and remembers everything. BOOOOM!!! He's back again.