Responses
They were not “given”, I think they took it by achieving high synchronization with high level cores. Since if you remember the pink head girlie could do that without the demon help
This was stated on chapter 101, ''We had originally promised the ''king'' that this form would never be easily displayed.'' And this is the reason why I think that their demon form was also given to them?
Like the lesser demon betrayed the kings ?
I think that those new heroes was also given the power of demon to defeat the demon that has been with the mc