Which seinen manga featuring Kei Kurono, and Masaru Kato, did Hiroya Oku write?
Gantz:  "Gantz" tells the story of Kei Kurono and Masaru Kato, both whom died in a train accident and become part of a semi-posthumous "game" in which they and several other recently deceased people are forced to hunt down and kill aliens armed with a handful of futuristic items, equipment, and weaponry.
i don't know