The young girl Kagami Ai bears the duty of fighting against a monster called Yodomi. One day, while undercover at school, she is discovered by her classmate Akira during her transformation and battle with Yodomi. Curious and drawn to the scene, Akira appears at the battlefield and is ultimately taken hostage. To protect him, Ai is captured by Yodomi's tentacles and her body is violated. Can she defeat Yodomi and save Akira? Or will the outcome lead only to tragedy?