"I am going to sleep," Arthur drawled as he dragged his feet up the stone stairs, "For one thousand years."

Merlin was only half listening - he was focusing more on trying to balance most of Arthur's weight on his shoulder, armour included, whilst not tripping over his feet. It was a good day for him if he could manage not to fall over on his own, let alone when he was dragging around a prat of a king who should have been in bed two days ago, so he simply huffed out a "Yes sire," and adjusted Arthur's arm over his neck so that it was more comfortable.

"Ugh," said Arthur as they reach the top of the stairs. He was one of those rare people who become more vocal when they are tired rather than less. "This is hell. Real hell. I feel sick and I'm too hot and I can't see straight. Merlin, I don't like it, make it stop."

Merlin grit his teeth, heaving Arthur up the last few steps. "I told you when you came back from the Iron Rocks that you were going to be ill and you needed to rest," he said. "And what did you do? Ignore me as usual."

Arthur and his knights had journeyed to the Iron Rocks at the very edge of Camelot's lands to repel some particularly troublesome bandits. The Iron Rocks were by the sea and the weather had been wintery and foul, so Merlin was not at all surprised when Arthur came back with a cold and a foul mood. Instead of heeding Merlin's warnings and general disapproval, he had attempted to soldier on and threw himself and his knights into some particularly gruelling training schedules. And now he was spluttering, coughing, sweating everywhere and so exhausted he could barely put one foot in front of the other, and it was all his own damn fault as far as Merlin could see.

"Shut up," said Arthur, but there was no heat to it. He sniffed and dragged his feet some more as they ploughed down the corridor to his chambers, then brightened up. "Still," he added, "At least I gave Gwaine a fair fight."

"You almost fell flat on your face when Gwaine gave you that last blow," Merlin snapped. He said it a little more viciously than intended, but felt this was fair – his heart had practically stopped when he'd seen Arthur collapse to the ground and it had only started again when he'd rushed over to find Arthur attempting to sit up and complaining that he felt dizzy.

"Bah," said Arthur, and stumbled into a wall. Merlin tutted and righted him.

"The great king of Camelot, felled by the flu," he teased, trying to lighten the mood. "The kingdom is doomed."

Arthur, instead of teasing back, muttered a quiet, "Don't be mean," and gently headbutted Merlin in the shoulder. This was so unlike him that Merlin started feeling worried all over again. He squeezed Arthur's arm in silent apology and tried to quicken their steps.

They got to the door of Arthur's chambers in a tangle of limbs, with Arthur coughing miserably into Merlin's face and Merlin biting his tongue so as not to say something rude. He managed to edge the door open and pushed them both through it, dropping Arthur as gently as possible into the nearest chair.

"Armour off and then bed," he instructed, and leaned forward to undo Arthur's breast plate.

"I have a headache," Arthur complained in response to this, and leaned his elbow on the table, putting his face in his hands. Merlin refrained from rolling his eyes and instead rifled around in his pocket, pulling out the bottle of headache remedy he had pilfered from Gaius earlier.

"Drink," he said, and waved it in front of Arthur until he looked up.

Arthur frowned at it. "Do you always carry around headache potion with you?"

"Have to when I'm manservant to you," Merlin countered, smiling, and pressed the potion into Arthur's hands. "Drink up."

Arthur uncorked the potion and drank it in one gulp. Merlin focused on removing Arthur's armour without him having to move too much, and for a while there was a comfortable silence between them.

Arthur broke it. "You brought it with you because you thought I'd need it today," he slurred. He sounded drowsy, and Merlin recalled suddenly that the potion was a soporific as well as a pain reliever. He hurried to remove the rest of Arthur's armour.

"Thought it might come in useful," he said, after a pause.

"You thought of me," Arthur said, as if this was simply unimaginable.

Merlin thought of a number of answers, rejected them all, then said instead, "Going to take off your chainmail. Lift your arms."

Arthur did so, obediently. "My headache's gone. You're the best manservant in the world," he said, his voice half muffled by the mail.

Merlin raised his eyebrows, carefully lying the chainmail on the table. "You really must be ill if you saying things like that."

Arthur huffed out a laugh. He looked a wreck, his body slumped, face pale and sweaty, golden hair sticking up at all angles. Sometimes, very rarely, Merlin got glimpses of the child Arthur had been before Merlin had known him. He looked like a five year old boy now, all sleepiness and sulkiness and a little bit of mischief. Merlin restrained himself from smoothing down his hair.

"Bed rest," he ordered, and looped Arthur's arm around his shoulder. "Come on."

Arthur groaned, but went willingly. He was lighter without the armour, but drowsier. By the time he was sitting on the bed and Merlin had taken off his shoes, his eyes were almost closed.

"Merlin," he murmured. "You'd think of me, wouldn't you?"

"Lie down," Merlin replied, ignoring him. He went to open a window a crack, though it was chilly outside.

Arthur shuffled amongst his covers. "If I was asleep a thousand years, I mean," he said. "You'd think of me?"

Merlin glanced over at Arthur from his spot by the window. For a moment he'd felt his spine crawl, as if a cold breeze had whipped into the room. He looked away, closed the window again. "Of course I would," he said, and was surprised to hear how sombre his voice was.

"What about one thousand, four hundred and twenty-seven years?" Arthur said.

Merlin looked back at him. Arthur's eyes were suddenly wide open, staring up at the ceiling blankly, as if he were seeing something outside of the world. Merlin felt the shiver down his spine again. He went over to the bed, suddenly craving Arthur's closeness, and perched on the end of it. He wanted to touch Arthur's arm, or hold his hand, something to remind him of the simple physicality of the man in front of him, but he felt restrained by shyness, even now.

"Bit of a specific time frame," he commented, sounding as light as he could.

Arthur turned round blue eyes to him. "But would you wait?" he said. "All those years?"

There was a sudden lump in Merlin's throat. He didn't know why, these were fevered ramblings from a man who'd pushed himself too far, that was all. And he was safe, and would recover. There was no reason for Merlin to feel suddenly so grieved.

"I would wait," he promised. "I would think of you."

Arthur's eyelids drooped, as if he'd gotten what he wanted, and he relaxed into the cushions. His coughing had stopped, Merlin was glad to hear.

"Sounds lonely," Arthur said after a long pause.

Merlin didn't know what to reply. "Yeah," he said.

"Yeah," echoed Arthur, and took Merlin's hand. His touch was warm and soft, and Merlin almost jumped at the shock of it. He stared down at Arthur's hand, at the tanned skin against his own whiteness, Arthur's little finger curled unconsciously around his.

When he looked up again, Arthur had fallen asleep.

He remembered it afterwards, after he had thrown the sword back into the lake and let the boat carry his dead king away from him. He remembered it, and counted the years, months, weeks and days from there, religiously. He calculated how long he had left to wait when it all got too much for him, and in his darkest hours this gave him comfort. He knew that Arthur had seen, briefly, his torment. He never doubted that at all.

And then, on that same day one thousand, four hundred and twenty-seven years later, he sat on the bank of the lake and saw the great tower of Avalon glow, and he watched his king come home.

"For even the very wise cannot see all ends."

J.R.R. Tolkien, The Fellowship of the Ring