It happened for the first time in the supermarket two weeks after Arthur crawled, chainmail-clad and sopping wet, out Lake Avalon.

Merlin had woken up a few times in the night, of course, with a start and a horrible creeping feeling that Arthur had disappeared in the night and he was alone once more, but that was always rectified by the turning of his head to find Arthur curled around a pillow next to him. His heart always let out a deep sigh of relief.

But this time he was awake, conscious, buying milk and eggs and the chocolate bars Arthur liked so much that the thought occurred to him – how did he know Arthur liked chocolate? Arthur was dead.

Dysphoria settled in his mind with unsettling ease. Merlin dropped what he was holding, and he heard the cracking of eggshells on the ground beneath him. Arthur wasn't dead, Arthur was back at his Manchester flat, watching the news. He'd have a whole new list of complaints about modern government by the time Merlin got him.

Arthur was a body at the bottom of a lake and he would never return. Merlin was waiting for a ghost.

"You have to pay for those, you know!" A snide, nasally voice called after Merlin as he bolted from the store at top speed, running or flying he wasn't sure, he just knew –

Nothing. He knew nothing.

"Merlin?"

He didn't know how long it took him to get home, but it seemed like it was only a moment later when Arthur, messy and golden, appeared in front of his eyes, voice concerned and suspicious and Merlin didn't even know he was reaching out until his hands were running through Arthur's hair.

"I thought you were dead, oh, God, I thought you were dead," Merlin babbled, hardly coherent, holding onto Arthur so tightly the other man started to cough.

"Merlin, Merlin – I'm not dead, not anymore," Arthur pulled Merlin's hands off of his neck with a gentle kind of force. Their fingers dangled together, brushing between them, but Merlin couldn't take the distance. He gripped them tight as he could in an attempt to anchor himself. "What brought this on?"

"I forgot you were here," Merlin whispered, jerking his eyes away from Arthur's. He realized how needy and pathetic he sounded, not remembering that Arthur was there with him. But it had been over a thousand years. "I thought I was still waiting."

Merlin hated himself as he felt the pinpricks of tears in his eyes fall onto his cheeks. Arthur's look was hesitant, as if he wasn't quite sure what to do.

"Shhh," his oldest friend whispered, reaching a tentative hand forward to rest on the back of Merlin's neck, much lighter than Merlin's grip had been. "It's okay. I'm here, and not planning on going anywhere any time soon."

"I'm sorry," Merlin shook his head as his tears hit the ground. "I just – I'm so scared."

Arthur's lips quirked up into a smile. "You're scared? I'm the one who just came back to life in what seems like an entirely different universe."

"I just – I keep worrying you'll die again, or you never came back in the first place. I can't die, Arthur. I don't want to be alone again."

"You were never alone, not really," Arthur shook his head, biting hard down on his lip. "I was always there. I promise. I don't remember anything of Avalon, but I know that if…if the gods gave me a choice, I would have stayed with you, watched over you. Like you did for me."

Merlin's hands reached out once more to engulf Arthur in a tight hug. Arthur's arms flailed for a moment before wrapping securely around Merlin's shoulders. Merlin sighed into the touch, burying his head in Arthur's neck.

"Don't leave again," Merlin whispered, so quietly he didn't know if Arthur could even hear the plea. "Please don't leave. I couldn't bear it."

"Should I just follow you around everywhere?" Arthur asked. There was a laugh in his otherwise thick voice. "Never give you a second's peace?"

"Well, that's a start," Merlin sniffed in what would have been pretentious and cool if he wasn't half-sobbing. Arthur just hugged him even more firmly, until all the breath drowned out of him. "I love you. I love you so much."

Arthur rocked backward. "I know."

"I was halfway to Avalon before I realized you were here."

"I'll always be here."

"I just – I still miss you. You're with me and I miss you. I miss you more than I love you."

"Why do you keep forgetting?"

"Because I just can't believe you would ever come back to me."