The Caerula Adamas plot a way to destroy the mysterious Battle Lovers. They also want to destroy the Defense Club, so as to cut down on club expenses. Thus, they declare that if the club members' scores on their final exams do not meet the average, the club will be dissolved. The Defense Club reluctantly gets to studying. Meanwhile, the student council also tries to scout the financially savvy Naruko to be their treasurer. When Gero offers him a salary during negotiations, Naruko casually agrees to leave the Defense Club. Soon, a monster appears, and the four remaining Battle Lovers must struggle to defeat it themselves.