She is the defender of her home-world. She is also the last survivor.

Finally cornered and confronted by Cross, the leader of the invaders, without any strength left to fight, the young girl is killed.

Cross and her brother, Chaos, leave behind the planet that they have utterly destroyed, as many others before.

On earth, Nagisa Kai, a high school student who wishes to become a professional wrestler is suddenly face to face with a hideous monster called a Gea. Rescued from the Gea's attack, Nagisa find herself in another dimension in the company of an Iczel robot who asks her to fight with him to protect the earth. Taken by surprise, Nagisa and the Iczel combine to become an Iczelion and quickly destroy the monster.

Back in our world, Nagisa refuses to have anything to do with all that and to fight against the invaders. In the middle of the discussion between her and the Iczel, Cross attacks but Nagisa still refuse to fight. She is rescued by Nami Shiina, a rock singer who is also Black Iczelion. At that time, Chaos brings Black Iczelion to another dimension where a Gea attacks her. Cross also bring Nagisa to another dimension.

Still refusing to fight, Nagisa reject her Iczel armour but without it, she can't even resist a single attack. She own her life to the arrival of Kiiro Iijima, Gold Iczelion and Kawai Kawai, Silver Iczelion soon joined by Nami who has killed the Gea attacking her.
Chaos arrives to rescue her out-numbered sister and flee with her.

Nami Shiina, Black Iczelion

Chaos sends his bodyguards, called Voids, to attack the various Iczelion. While Kawai, Kiiro and Nami each have to fight a Void to protect Nagisa, Cross arrives to finish once and for all with her chosen target.

Nagisa finds herself with some other students on the roof of the school where Cross begins to "play" with her but she still refuses to fight !

Kawai quickly kills her Void but she doesn't have enough strength left to continue the fight.

Black Iczelion's beam sword doesn't have any effect against her Void but finally, by concentrating her Iczelion Gravity on her sword, a very risky fighting technique, she manages to kill him.

Kiiro doesn't have any difficulty in defeating her opponent but it doesn't want to die and each time it stands up again more powerful than before ! The void finally transforms itself in a gigantic monster and comes back to our dimension, destroying buildings.

During that time, Cross is still playing with Nagisa. But when she starts hurting the other students, Nagisa finally accepts her destiny and decides to fight. She synchronises with her Iczel and becomes the "Normal Type" Iczelion.
Cross is totally surprised by the power of Nagisa and the speed of her attacks. She is defeated quickly but her spirit joins the remaining Void and merge with it. The four Iczelion combines their power and manage to destroy the last Void.

Act II ends here with Chaos ordering all his fighting Geas to attack. After the ending theme, we just see a few pictures of the Iczelion destroying whole bunch of invading geas.