Code Geass: Akito the Exiled 1: The Wyvern Arrives.

The side story takes place in 2017 a.t.b., between the rise of the “Black Knights” organization and the return of the supposedly "dead" Zero. The setting is in Europe, where the European Union (E.U.) allied nations are being invaded by the overwhelming forces of the Holy Britannian Empire. On the verge of defeat, the E.U. army forms a special unit known as “W-0″, of which a young pilot named Akito Hyuga is a member. Leila Malkal , a former Britannian Aristocrat comes to the E.U.'s aid, commanding the “Wyvern” Knightmare corps comprised of Japanese teenagers. They recklessly plunge into a battlefield, where the survival rate is extremely low, at about 5% only. They fight for their freedom and for a "home" to which they can return.