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Merlin pressed his palm against the golden sun emblazoned on his left shoulder, feeling the familiar warmth pulse beneath his skin. The mark had appeared on his sixteenth birthday, just as it did for everyone—a symbol that would match exactly with his soulmate's. But while most people spent years searching for their other half, Merlin had known immediately.
The crescent moon adorning Arthur's shoulder blade was impossible to miss during training sessions, when the prince stripped down to his undershirt and sweat gleamed on his skin. Sun and moon, light and shadow, magic and crown—they were meant to be two halves of the same whole.
If only it were that simple.
"You're distracted again," Arthur observed, lowering his sword as Merlin stumbled during what should have been a basic sidestep. "Are you ill?"
"No, sire," Merlin replied quickly, adjusting his grip on his own practice blade. "Just thinking."
"Well, stop it. Thinking will get you killed." Arthur's tone was teasing, but his blue eyes held genuine concern. "What's troubling you?"
Only everything, Merlin thought. How could he explain that every fiber of his being screamed that they belonged together, when magic was punishable by death and Arthur was destined to be king? How could he reveal that the servant Arthur barely tolerated was marked as his equal by the very forces that governed their world?
"It's nothing," Merlin said, raising his sword again. "Shall we continue?"
Arthur studied him for a long moment, then nodded. They resumed their practice, but Merlin could feel the weight of Arthur's gaze lingering on him between exchanges.
Later, as Merlin polished Arthur's armor in the prince's chambers, he found himself stealing glances at Arthur's exposed shoulder. The moon mark seemed to shimmer in the candlelight, and Merlin's own mark responded with a gentle warmth that made his breath catch.
"Merlin."
"Yes, sire?"
"Have you ever wondered about your soulmate?"
Merlin's hands stilled on the breastplate. "I... what do you mean?"
Arthur was sitting on the edge of his bed, unlacing his boots, but his movements had grown slow and thoughtful. "I mean, do you ever think about what they might be like? Whether you'll recognize them when you meet them?"
"Sometimes," Merlin admitted, his voice barely above a whisper. Every waking moment.
"I used to think it would be simple," Arthur continued. "Find the person with the matching mark, fall in love, live happily. But now I wonder if it's more complicated than that."
"How so?"
Arthur set down his boots and turned to face Merlin fully. "What if your soulmate is someone you can't be with? Someone whose station in life makes a union impossible? What if the gods have a cruel sense of humor?"
The armor slipped from Merlin's suddenly nerveless fingers, clattering to the floor. Arthur was on his feet in an instant, crossing the room to where Merlin knelt to retrieve the fallen pieces.
"Merlin? What's wrong?"
"Nothing, I'm fine," Merlin said, but his hands were shaking as he reached for the breastplate. "Just clumsy."
Arthur knelt beside him, and suddenly they were very close, close enough that Merlin could see the gold flecks in Arthur's eyes, could feel the warmth radiating from his skin. Close enough that when Arthur reached out to steady Merlin's trembling hands, their marks seemed to sing in harmony.
"You're not fine," Arthur said softly. "You haven't been fine for weeks. What aren't you telling me?"
For a moment, Merlin wavered. The truth pressed against his lips like a caged bird desperate for flight. But then he remembered Uther's cold eyes, the pyre that had consumed so many of his kind, and the words died in his throat.
"I should go," Merlin said, pulling back. "It's late."
Arthur let him go, but the concern in his eyes followed Merlin long into the night.
The attack came three days later, swift and brutal. Bandits had been plaguing the northern roads for weeks, but their latest assault was different—more organized, more vicious. Arthur had insisted on leading the patrol himself, and of course, Merlin had followed.
Now, as Arthur's sword sang through the air and men fell around them, Merlin found himself backed against a tree, a bandit's blade at his throat. He could use his magic—one word would send his attacker flying—but not with Arthur so close, not with the other knights watching.
The bandit's eyes were wild with bloodlust. "Prince's little pet," he snarled. "Wonder how much you're worth?"
"You're about to find out," Arthur's voice rang out behind the bandit. The man spun, and Arthur's sword found its mark in one swift, deadly motion.
But as the bandit fell, his dying breath carried a curse. His dagger, meant for Arthur's heart, went wide—and found Merlin's side instead.
"Merlin!" Arthur's cry seemed to come from very far away. The world tilted, and Merlin felt himself falling, the forest floor rushing up to meet him.
Strong arms caught him, cradled him. "Stay with me," Arthur's voice was fierce, desperate. "Don't you dare die on me."
"Arthur..." Merlin's voice was weak, blood warm on his lips. "I'm sorry."
"For what? You have nothing to be sorry for." Arthur's hands were already working at Merlin's shirt, tearing the fabric to reach the wound. "We need to stop the bleeding."
But as Arthur pulled the ruined shirt away, his hands froze. There, revealed on Merlin's left shoulder, was a golden sun—perfect, radiant, and unmistakably familiar.
The forest went silent around them. Even the other knights, approaching to help, stopped in their tracks as they saw what Arthur was staring at.
"No," Arthur breathed. "No, this isn't... you can't be..."
With shaking hands, Arthur reached for his own shoulder, pulling his shirt aside to reveal the silver crescent moon that had marked him since his sixteenth birthday. As if drawn by some invisible force, Arthur's mark began to glow softly, and Merlin's sun responded with warm, golden light.
"You knew," Arthur whispered. "All this time, you knew."
Merlin tried to speak, but darkness was creeping in at the edges of his vision. "Arthur, I—"
"Shh, don't talk." Arthur's voice was thick with emotions Merlin couldn't name. "Save your strength. We're getting you back to Camelot."
As Arthur lifted him, Merlin felt the world slipping away. But just before consciousness left him entirely, he heard Arthur's voice, soft and wondering:
"My soulmate. My impossible, wonderful soulmate."
Merlin woke to the sound of quiet voices and the scent of healing herbs. His side ached, but the sharp agony had faded to a dull throb. Gaius was there, of course, checking his bandages with practiced hands.
"Ah, you're awake," the old physician said with obvious relief. "How do you feel?"
"Like I've been stabbed," Merlin replied, then winced as the movement sent pain through his ribs. "Where's Arthur?"
"He's barely left your side for three days," Gaius said. "I had to threaten him with a sleeping draught to get him to rest. He should be back soon."
As if summoned by their words, the door opened and Arthur stepped in. He looked haggard, his hair disheveled and his eyes red-rimmed with exhaustion. But when he saw Merlin awake, his entire face transformed.
"Merlin." Arthur was at his bedside in three quick strides. "Thank the gods. I thought... when you collapsed, I thought I'd lost you."
"I'm harder to kill than I look," Merlin said, attempting a smile. But Arthur's expression remained serious.
"We need to talk," Arthur said. "About what happened. About what I saw."
Gaius cleared his throat. "Perhaps I should leave you two alone."
"No," Merlin said quickly. "Gaius should stay. He... he knows."
Arthur's eyebrows rose. "Knows what?"
Merlin took a shaky breath. This was it—the moment he'd been dreading and longing for in equal measure. "About the marks. About what they mean. About... about everything."
"Everything?"
"Arthur, I—" Merlin's voice broke. "I've known since the day we met. That we were... that the marks matched. But I couldn't tell you. How could I? I'm just a servant, and you're going to be king. The law, your father..."
"The law?" Arthur's voice was sharp. "What does the law have to do with soulmates?"
Merlin and Gaius exchanged glances. "Arthur," Gaius said gently, "there's more you need to know. About Merlin. About why he couldn't tell you."
"I don't understand."
Merlin closed his eyes, gathering his courage. When he opened them again, he lifted his hand, and without a word, a small flame danced in his palm.
Arthur jerked back as if struck. "Magic," he breathed. "You have magic."
"I was born with it," Merlin whispered. "It's not something I chose, Arthur. It's just... part of who I am. Like the mark on my shoulder."
The silence stretched between them, heavy with years of unspoken truth. Arthur stared at the flame in Merlin's hand, then at Merlin's face, then back at the flame.
"All this time," Arthur said finally, "you've been hiding this from me."
"I had to. Your father—"
"My father would have you executed." Arthur's voice was hollow. "And I would have been the one to carry out the sentence."
"Yes."
Arthur was quiet for a long moment. Then, to Merlin's amazement, he reached out and closed his hand around Merlin's, extinguishing the flame but not pulling away.
"I can't do this," Arthur said. "I can't be king and have a soulmate who practices magic. It's impossible."
Merlin's heart clenched. "I know."
"No, you don't know," Arthur said, his grip tightening. "You don't know because you didn't let me finish. I can't be king and have a soulmate who practices magic... alone."
"Arthur?"
"If you're going to be my other half, then you're going to help me change things. The laws, the kingdom, everything. We're going to make Camelot a place where magic and crown can coexist."
Merlin stared at him. "You can't be serious."
"I've never been more serious about anything in my life." Arthur's blue eyes blazed with determination. "Did you really think I'd let something as trivial as my father's prejudices keep me from my destiny? From our destiny?"
"It's not trivial, Arthur. It's treason."
"Then we'll commit treason together." Arthur brought Merlin's hand to his lips and pressed a soft kiss to his knuckles. "Sun and moon, remember? We were made to balance each other."
As Arthur spoke, their marks began to glow again—gold and silver light intertwining in the dim room. And for the first time since he'd discovered the truth about his soulmate, Merlin allowed himself to hope.
"Together," he whispered.
"Together," Arthur confirmed. "Always."
And in that moment, as their lights merged and their hands intertwined, Merlin knew that destiny was finally beginning to unfold as it should—not easily, not without struggle, but with the promise of a future neither of them would have to face alone.
The sun had found its moon, and the moon had found its sun. And together, they would reshape the world.