It's been 50 years since dungeons and unknown monster suddenly appeared in the world. When they arrived an intense invasion and conquest in killing all humanity had already taken place. As a result, the people were forced to fight back, which started the resurrection of those people with supernatural power. They were called ASCENDER. Since then, the people's strength to survive has gradually returned. But 50% of humanity's population is gone. But even so they still tried to survive which resulted in a new Era of human kind in which strong ruled the weak.