Frieren's demons

With the hiatus in Frieren's manga and the delay in releasing the second season, I decided to venture into the theories on reddit and would like more people's opinions. SPOILER ALERT. In Frieren's manga: Beyond Journey's End, we know that demons are creatures made of pure mana, which have the ability to disintegrate and manipulate others, being devoid of true empathy. They disguise themselves as allies to deceive humans and have a very different relationship to magic than humans and elves. The great lone demon, in conversation, suggests that demons evolved from magical creatures who learned the human language to deceive their prey. Additionally, it is revealed that demons have no family ties and are abandoned shortly after birth. Another important piece of information is that, thanks to Aura's powers, we know that demons have a soul, although it is "different" from human souls. Personally, I believe that Frieren's demons resemble, to some extent, the orcs from The Lord of the Rings. Orcs are not creatures that were born naturally, but were created — being elves tortured and corrupted with part of Morgoth's essence/soul. Similarly, demons could be a creation of the Demon King, possessing part of his soul but no physical body. Perhaps all magical creatures are creations of the Demon King (although there are no clear indications of this). It's interesting to note that the Demon King, like Match, sought consistency with humans, which opens up the possibility that demons and even the Demon King himself are not entirely evil.