One of the largest regions of the Royal Demon Nation, the Demonic Academia Region, was closest to the Demon Emperor Domain.
This region was under the management of four Demon Institutes: named, Evergreen Demon Institute, Battle Demon Institute, Black Mountain Demon Institute, and Royal Demon Institute.
These four institutes were under the direct juridical of the Demon Emperor Domain, and non-other have any authority over them and they have the most precious resources in the entire Almighty Demon Empire.
Whether it was resources, skills, or techniques, everything was top-notch.
That's also what made these institutes so alluring to the demons.
Furthermore, it was also an ironclad law of the Royal Demon Nation that any young demon who could cultivate had to spend at least fifty years in one of the institutes to learn about different fields they'll be serving in the future.
No one could overstep this hurdle, even the Grand Demon Tribes.
