R^2【rise R to the second power】 ; Rise R to the Second Power ; R²

From ADV: A pizza delivery boy must save the world! Young Kenta Akagi has never been anywhere except for his hometown of Lutzheim, where he currently ekes out an existence as a pizza delivery boy. Faraway places, strange foreign folks, the wars they fight, and the adventures they have are just stories to him, until he meets a young girl - the kind of girl that wars are fought over! People seem afraid of her, but Kenta doesn't understand why. All he knows is that he seems to remember her from somewhere, and that he has to protect her no matter what!