Unanimous

The disappearance of a young neko and an ordinary boy could be seen as a rebellious act, but when the most innocent girl of class 502b also vanishes, everyone starts worrying. Because the adults don't take action, the pupils decide to take matters into own hands. They go looking for their missing classmates.
Somewhere far away, in the kingdom of Agmardor a young fairy is locked away in the castle of a dangerous demon, someone who was thought to be a simple human. Blinded by fury and resentment the demon refuses to let her leave the castle ever again. He needs her for a plan he desperately wants to succeed.
But something unpleasant is awaiting him.
502b is not going down without a fight.