What if the demon king visited Teyvat

**Chapter 1: The Return of the Demon King**

Two thousand years had passed since Rimuru Tempest, the Demon King and ruler of the Tempest Kingdom, left the world of Teyvat. In the world of Tensura, time flowed relentlessly, filled with the peace he had built alongside his friends and subordinates. Yet, in his heart and mind, a lingering curiosity remained-about the world he once visited and the seven Archons he had aided during the war of the gods.

Meanwhile, in Teyvat, the war of the gods had faded into legend, and many no longer remembered the name "Azathoth." The remaining Archons continued to maintain the balance of elements and power in their respective realms, never forgetting the shadow of the mysterious strength that once aided them.

However, one night in his throne room, Rimuru felt a strong urge within him. It was not just curiosity, but also from Ciel.

"Master, it seems it's time to return to Teyvat," Ciel's voice echoed in his mind, soft yet insistent. "Many things have changed, and... it seems the world needs your strength again."

Rimuru smiled faintly. "I know. Alright, let's see what awaits me this time."

With a flicker of intention, a magic circle appeared beneath his feet, and in the blink of an eye, Rimuru vanished from the world of Tensura, returning to Teyvat.

***

When Rimuru opened his eyes, he found himself standing on the edge of a beautiful valley with a vast landscape stretching before him. The blue sky of Teyvat greeted him warmly, and the wind whispered as if recognizing his presence.

"Teyvat... It's been so long," Rimuru murmured as he gazed at the land he had left behind two thousand years ago. Much had changed. Life seemed more peaceful, yet he could sense that there were still hidden things beneath the calm surface.

"Master, to the west, there is someone intriguing," Ciel warned him.

Rimuru immediately turned his gaze, and in the distance, he saw a figure-a girl with long, golden hair, dressed in typical adventurer attire. Her eyes were filled with determination, but behind that, there was weariness and profound sadness, like a warrior who had been searching endlessly without ever finding.

Rimuru stepped closer. As he approached, the girl appeared cautious. Her small hand gripped the sword sheathed at her side tightly, her golden eyes focused intently on Rimuru with a mixture of intensity that reflected her experience and years of resilience.

"Who are you?" Her voice was firm, yet gentle. There was a deep-seated suspicion in her gaze.

Rimuru paused for a moment, smiling lightly. "My name is... Rimuru tempest," he replied, playfully using His real identity . "And you are?"

The girl hesitated, unsure whether to trust him. "I am Lumine," she answered briefly, but there was something deeper in that introduction-a sense of exhaustion from a long journey, loss, and an endless search.

Rimuru sensed the emotions swirling around her. "You seem like someone who has been through a lot," he said softly, trying to ease the tension.

Lumine tightened her grip on her sword, but she did not strike. "I am searching for my twin brother... Aether. It has been far too long since I lost track of him. Are you one of them?" Her tone sharpened, referring to the gods who had separated her from her brother.

Rimuru shook his head. "I am not one of them. I am merely a traveler... much like you, perhaps."

A silence hung between them for a moment, the gentle wind weaving through the trees, carrying the fresh scent of nature. Yet there was uncertainty in Lumine's eyes and an unmasked frustration. Still, there was also a sense of relief within her-relief in meeting someone who, for the first time in a long while, was not trying to manipulate or play with her.

Lumine looked down, trying to hide the emotions that began to surface. "Everyone... always has a hidden agenda," she murmured, almost inaudibly.

Rimuru stepped one step closer, speaking gently, "I understand that feeling. But I am not here to play games with you, Lumine. I am here simply because... I was called back to this world."

Lumine looked up, their gazes locking onto each other. "Called back? Have you... been here before?"

Rimuru smiled faintly. "A long time ago, before Teyvat changed as it is now. Perhaps we can share stories. Who knows, maybe we can help each other."

There was something in Rimuru's tone that made Lumine feel a bit more at ease. Though she was not fully convinced, a flicker of hope emerged within her. Something about the figure before her felt different-mysterious yet trustworthy, calm yet full of strength.

"I will listen," Lumine finally said, relaxing her grip on her sword.

Rimuru smiled warmly. "Let's start with your journey, and maybe I can offer a bit of assistance."

With that, their conversation began. Their first meeting, seemingly simple, held great potential-a connection that not only linked two weary souls but also opened a new path in a grand adventure that would change the fate of Teyvat forever.