Nagisa is an ordinary schoolgirl who gets sucked into the battle between the Cthulhu and Iczer-1. It begins with Iczer-1 whispering her name in her dreams. That day, she encounters a strange, pointy-eared blonde (Iczer-1) on the way to school, who disappears before she can point her out to her friend. From there, things only get weirder, as she suffers what she believes are hallucinations in class, and is accosted by her classmates on the roof of her school, all wearing strange masks with eyes in the mouths. Strong emotions are usable by the Cthulhu and Iczer-1 as a power source. Nagisa is a very emotional girl, and therefore her emotions could be harnessed into a powerful weapon. This is demonstrated when she is incorporated into the Iczer Robo and becomes enraged over the deaths of her parents. This turbo-charges the robot with enough energy to kill Cobalt.

(Source: Wikipedia)