A space where you is confined. There is one plain, sterile bed, and one wall is made entirely of glass. The door is heavily locked. In short, it was a space like an exhibit at a zoo. Occasionally, for research purposes, their strength and body are used as one pleases, and they are even subjected to pain. Sometimes they are forced to fight other creatures to measure their stamina and abilities. Up to this point, it is no different from any other research subject. However, there is one single, unique difference. That is the fact that you is a madman.