Cross Ange: Tenshi to Ryuu no Rondo S01

Using a power known as Mana that people discovered, they were able to put an end to all wars, hardships, and hunger, and turn the world into a utopian city for living. The elder princess of the Misurugi Empire, Princess Angelize, also lives in this peaceful and carefree world. The people of her land love her, and she is soon to become the heir to the throne. However, at the same time, Angelize becomes aware of a terrible truth. She realizes that she is actually a Norma, a person who cannot use the power of Mana, and society treats them like objects. After being rejected by her land and people, she flees to a remote island in the middle of the sea and hides herself from everyone. But on this island, she encounters a group of Norma girls who know nothing but war in their lives. They use large robotic machines called Barameirs to fight dragons that invade their world from another dimension. Ange, who has nothing to lose, joins this group.