Gunslinger Stratos: The Animation

ガンスリンガー ストラトス -THE ANIMATION-

In 2115, the land once called Japan has become the strictly governed 17th Far East Imperial City Management District, where a degenerative illness reduces its victims to sand. Ordinary student Tohru Kazasumi is pulled into Operation Stratos, a war against a parallel world called Frontier S, where each fighter must face an alternate version of themselves. Tohru and his childhood friends Kyoka and Kyoma Katagiri and Shizune Rindo take up arms as their duplicates from the other universe come for them. Adapted from the arcade gun game.