It's a long time after the battle before Arthur has the chance to sleep. There's walls to be secured in the captured fort, captives to be imprisoned and questioned, wounded men who need to see their commander still standing and the dying who need a hand on theirs as night falls. By the time things are starting to calm down, he's swaying on his feet.
"Sire," Leon says, grasping his shoulder. "There are rooms upstairs. Get some sleep."
Arthur tries to knuckle the tiredness out of his eyes. "Do we know where Colgrin's gone?"
"He's fallen back towards Eoforwic. Sire, you need to sleep. Colgrin won't regroup for a few days and you can't lead us if you're exhausted."
Arthur shakes his head, trying to focus. "My men-"
"Will manage without you for a few hours."
Unwillingly, he gives in and hauls himself up to the top floor of the keep. It had been the home of one of his father's allies before the Saxons came, a link in the wall that protected Camelot. But Margan is dead and gone, and they are fighting to survive, not just to protect their borders. The place shows all the signs of possession - torn scraps of old tapestries still hanging along the tops of the corridors, doors wrenched from their hinges, stains on the stairs.
He finds his room by guesswork as much as anything. He knows it's his because Merlin is in it, facedown and snoring on the bed. There's a bath steaming by the hearth and a low fire burning. He manages to heave the door back into place, giving him some privacy, but it makes his shoulders burn. He feels like an old man, and while he's not a boy now, he supposed to be young.
He wants to get his armour off more than anything, but his fingers fumble on the buckles and he can't reach them all. Stumbling to the bed, he pokes Merlin in the side until he moans and wakes up, frowning.
"Help me with my armour."
Merlin blinks at him before burying his face back into the pillows. "G'way. Sleeping."
Arthur pokes him harder. "Get out of my bed and help me with my armour."
"Find your own bed. This one's mine. In fact, find your own room."
"If this isn't my room, why is the bathwater still hot?"
Merlin lets out a long, put-upon sigh, and sits up, wincing. Arthur holds his arms, waiting, and Merlin's eyes narrow and flash golden.
Arthur's armour hits the wall behind him with a clang, and he growls, "Merlin!" He knows about the magic now, can't think of anyone who doesn't and what does it matter now that Camelot is falling, but it's rare for Merlin to be that ostentatious. "I can't wear it if it's dented."
"It's not," Merlin says, eyes closing again. He flops back onto the mattress and then winces.
Arthur pulls him up, ducking the flailing arms and peels his shirt off. Merlin was out of the action today, or should have been. "Where are you hurt?"
"Nothing new," Merlin says, letting his arms fall again. "Old wounds ache in bad weather, don't they?"
"Not that badly," Arthur tells him, reaching round to press his hands onto the mess of scar tissue on Merlin's back. Six months since Verlam, and still Merlin limps after a few hours. The army chirurgeons say he may never fully heal, but he won't go back to Camelot, to Gaius, won't leave Arthur. "Did you have a bath?"
"It's for you."
"Idiot," Arthur says and drags him across the room, wrestling the rest of their clothes off as he goes. A year in the saddle, moving from battle to battle, lucky to have any roof at all, and he's come to accept that privacy is a luxury of peacetime. He doesn't blush to see any of his men naked now, especially not Merlin, who is always there and always has been.
The touch of warm water against his skin makes him throw his head back with a groan, and he sinks into it slowly, his breath catching as it slides over his aching legs and up his back.
"Sure you and your bath tub don't need to be alone together?" Merlin inquires, but he's making little mumbly pleasure noises of his own so Arthur ignores him. For a few moments, he just lies back and lets the day go, imagines he's back in Camelot and that his father is still alive and there's nothing worse to worry about than Morgana's latest feud.
Then a wave slaps over his chin and he opens his eyes to see Merlin sliding under the water at the other end of the bath. Swearing, Arthur drags him back up by the arm, only to be glared at indignantly.
"I was washing my hair. I didn't fall asleep."
Arthur favours him with a sceptical glare. "Of course you didn't." Merlin always looks ridiculous when he's drenched - hair slick against those preposterous cheekbones of his, his eyes peering out from between spikes of wet fringe, like somebody had dunked a puppy. Arthur grins at him and says, "You look like a drowned ferret."
Merlin sticks his tongue out and tries to splash Arthur. It's half-hearted, but Arthur has to reach out and grab his bony ankle to drag him under. Merlin goes down with a yelp and then resurfaces spluttering while Arthur is still laughing. Within a few minutes, half the water is on the floor and they're both trying to wrestle and failing, hands slipping on wet skin, sliding off arms and onto ribs and hips. Merlin's all knobbly bones and warm skin beneath his palms and Arthur eventually stops trying to grab him and just wraps his arms across the idiot's back to stop him from squirming. "You're supposed to be soaking that wound."
"You started it," Merlin protests and he's sounding sleepy again, slumped against Arthur's chest. "Bully."
"Ingrate," Arthur mutters back. "See if I share again."
Merlin lets out a sceptical scuffle and Arthur sighs and turns him round until Merlin's leaning back against him, his back pressed warmly on Arthur's chest, his neck close enough to breathe on.
"Close your eyes," Arthur murmurs needlessly, and scoops up a handful of water. He's seen Merlin struggle to raise his arms when he's tired lately, and he can do this for him.
Merlin sighs and presses back as Arthur tips the water over his hair, and Arthur has to fight back the urge to press his lips to Merlin's neck. There's a line they haven't crossed yet, though their lives are so tangled together in all other ways. They're so entwined that the few unspoken things left terrify Arthur: they never speak of what Uther would have done if he'd known about Merlin, or about Morgana, or about the fact that Merlin only warms Arthur's bed in the most literal of ways and how easily that could change.
One day soon, Arthur thinks, sliding his hands down under the water to rub at Merlin's aching back, he'll decide there's no more use in caution. He'll forget that he's a king and has a kingdom to build one day and he'll live for the moment: stop rolling away, stop pulling back, stop biting his lip against words his father would never have spoken. One day soon, he'll stop pretending that he isn't hard and desperate when Merlin's this close, stop telling himself that he won't find anything if he slides his hand round to touch Merlin.
Merlin turns his head, nuzzling into Arthur's shoulder, and murmurs, "Your hands feel good."
Perhaps today will be that day. His hands are shaking, so he presses them flat against Merlin's ribs and whispers, "How good?"
But Merlin's asleep again, his breath steady and warm against Arthur's chin. Sighing, Arthur holds on for a moment, gathering the strength he'll need to get them both out of here and into the bed, which will be warm, at least until the morning comes and the war goes on.