Giniro no Olynsis

Giniro no Olynssis (銀色のオリンシス, Giniro no Orinshisu) is a Japanese light novel created by Hitomi Amamiya, with illustrations by Hisashi Hirai. It was first serialized in the seinen magazine Dengeki Maoh in November 2006. An anime adaptation directed by Katsumi Tokoro and produced by Toei Animation aired in Japan from October 5, 2006 to December 21, 2006.

Plot
In the future of year 3567, a supernatural barrier called the Olynssis barrier, enveloping all of Earth and disrupting its space and time. The planet is also being overrun by organic machines called Gardeners, which seek to exterminate all humans in order to "save and preserve" the planet. Tokito Aizawa is part of a group of hunters who destroys Gardeners and sells the scraps. Although, after encountering a girl named Tea, who constantly calls him "Koichi", and her giant machine, Silver, his life becomes more complicated.