Anime Profile: Fafner in the Azure: Dead Aggressor

In the seemingly peaceful remote island of Tatsumiyajima, the locals have prepared to face a strange and deadly enemy. The world has come under attack from strange and powerful alien beings called "Festum." Tatsumiyajima, a floating island, was the only safe haven left in the world, because all of the other countries have been destroyed by the Festum. The Festum attack cities with their giant purple bubbles of death, their assimilations, and their green crystals.

Now, the last line of defense lies with Tatsumiyajima and their trump card, Fafner, a powerful mecha that guards the final treasure of mankind. A teenager named Soushi Minashiro becomes the guide for Fafner's physical pilot, Kazuki Makabe, and risks everything to protect humanity from the Festum. But what are the Festum, and what are they really after?

Soushi's best friend, Kazuki Makabe, is the second pilot of Fafner. The first pilot's name was Kuramae, but she died during the first attack of the Festum on Tatsumiyajima. All of Kazuki's other friends except Soushi are pilots of some kind of mecha. Soushi is the operator of the Siegfried system, a computer that allows him into the minds of the pilots to help them when they fight.

At the end, Soushi is assimilated by the Festum and stays with them to try and teach them emotions. Tsubaki, Soushi's little sister, becomes the core of the island to help protect them (in other words she assimilates with the island).