Koukyoushihen Eureka Seven: Pocket ga Niji de Ippai

Renton, son of scientists, and Eureka, a girl who can't live under the sun, are raised together when very young and become very attached to each other. One day, Eureka is taken away. Powerless at the time, Renton vows to rescue her. He enters the military and is soon is assigned to the Independent Youths Unit 303 of the First Mobile Forces thanks to his exceptional performance alongside his Nirvash, a bio-mechanical armor/control system. Unknown to Renton, lies a plot to extinguish the alien invasion that is currently happening involving not only him, but Eureka too. (Source: ANN)In the year 2054, there is a boy on board the Gekko, the mother ship of the 303rd Independent Horde under the command of Holland Novak. His name is Renton and his dream is to ride into battle on his Nirvash. He has resolved to one day rescue Eureka, his childhood friend who was kidnapped eight years ago, and to return home.