One day, all the eighth grade students were transferred to another world.

The princess of the other world summoned them to make up for their lack of strength. The students are threatened and decide to follow the princess, and they are made to take a magical power test to determine their abilities. While everyone is sorted according to their results, Kokubun Kento's result is a flop.

Judged as useless, he is expelled. However, there is actually a tremendous ability lurking within Kento...

The life-size eighth grader Kento, together with his fellow skeletons, aims to rescue his classmates!