Anos Voldigold died 2000 years ago, creating a barrier that has sealed off the various races from each other. Then last month, he is reincarnated into the world. Luckily for him, there has been a demon lord school established. To help find the reincarnation of the demon lord to once again rule the demon realm. So Anos gets to go to school with the descendants of his former allies from 2000 years ago. Of course, this will work out great.