Gantz Reika Shimohira Cosplay

 Gantz (ガンツ Gantsu?) is a Japanese manga series written and illustrated by Hiroya Oku. Gantz tells the story of Kei Kurono and his friend Masaru Kato who die 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 of equipment and weaponry. - source:  http://en.wikipedia.org/wiki/Gantz