What was the story behind the Demon King's ending?

Answer 1

" The Great Demon King " is a fantasy-modern magic novel written by the author, Defiant Heaven. The general plot of this novel is as follows:

The legend of a cowardly youth surpassing himself step by step, walking towards evil, walking towards the Demon King…
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The Great Mage of MCMAU was a fantasy sword and magic novel written by the author, Gaudy Shen Mo. The general plot of the novel was:

Ten thousand years ago, after the Battle of Gods and Demons, a new story had begun on the Magic Martial Continent at dawn.
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The Magic Empire Reborn was a fantasy sword and magic novel written by the author, Capturing the King in One stroke. The general plot of the novel was:

A mage who should have died, a mage who was still at the bottom of the mage world after living for more than a thousand years, a mage who could not keep up with the times, a mage who was alone and had nothing. On a day that could not be considered a sunny day, a dimensional dragon that traveled through the universe accidentally sneezed, and then our protagonist was reborn. Could he break the shackles of fate, lead an era, suppress countless geniuses, and establish an invincible Magic Empire?
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" Has the Demon King Awakened?" was a fantasy epic fantasy novel written by author Fujisakura Yuki. The general plot of this novel was:

The Great Wizard Robin had left behind a prophecy: The era of the Demon King is coming. He will be born from the illegitimate child of the king. Darkness will envelop the capital. Is the decaying kingdom that was granted by the gods to welcome its final glory? How should the Magic Knights get rid of the so-called illegitimate child? Wizards, sorcerers, monsters, the human world, the demon world, and the wizarding world all changed because of the birth of the demon king. The faith of the past was on the verge of collapse in human nature, and the arrival of the Demon King was inevitable. The Fairy Clan didn't dare to sit still and wait for death. They weren't afraid of the Demon King, but the more terrifying foreign races. After the war thousands of years ago, would they make a comeback? Ordinary people also have extraordinary aspects. In order to become stronger, I embarked on an adventurous journey. Even if the whole world gave up on me, I would not give up on myself. The dust on my dusty throne rose. It was waiting for the day its master returned.
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" The Highest Mage " was a fantasy sword and magic novel written by the author, the God of Magic. The general plot of the novel was:

Soaring in the kingdom of magic, magic is king, magic is respected, and you can see the world in the sky and under the sea.
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" When a Hero Reincarnates as a Demon King " was a light novel by the author, Immortal Blade. The general plot of this novel was:

When a hero attacked the Demon King, he was cursed by the Demon King before he died and became the new Demon King. He was abandoned by the whole world. People pointed the spearhead of the war at him. After he defeated the darkness with light, they let him die in the light. However, after destruction came rebirth. When the new Demon King was reborn in a certain world in the universe, his adventure had just begun…
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" My Demon King Can't Save the World " was a fantasy sword and magic novel written by the author, Zhen Ao. The general plot of the novel was:

Hmm…How should I tell the story?
This was the story of a demon king who did not want to conquer the world.
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" The Demon King's Promotion " was a fantasy sword and magic novel written by the author, Lost Dream. The general plot of the novel was:

Everyone was envious of the domineering position of the Great Demon King, but so what? I don't want to become one! There was no choice in life! Some people had to become great demons after reincarnation!
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Magic Martial World was a fantasy sword and magic novel written by the author, Wang Di. The general plot of this novel was:

The magic world had always been peaceful and stable. With the fall of the new emperor, the power of national leadership once again became the target of competition among various forces. The young girl, Mo Yushan, had inherited the power and possessed a unique Judgement magic power. He was tasked with maintaining peace and justice in the Magic World and fighting against activities that destroyed order. The cold-looking young man was Ye Miqi, the heir of the Ye family. He had the title of 'Blood Branch', and was known for his powerful strength and cold personality. The battle for the throne had affected the entire magic world. Their encounter had created a different fate for the two of them. On the same path, the two of them met, knew each other, and fell in love. But in the end, they were separated by the power struggle. For the stability of the country, the two of them began to walk different paths.
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" The Last Demon " was an Oriental fantasy novel written by the author, Yisha Shengji. The general plot of this novel was:

He was the last demon in the world! There were nine versions of himself in his body! He had both the power of a demon and a god! When his nine lifetimes returned to one, he would be the ultimate Demon God! His name was Demon Life.