He wakes up and he’s burning, he's burning, he’s—
And Arthur is there, Arthur is the only cool and solid thing in the world, Arthur with his knit brow and his rough hands, and he’s—he’s leaving, promising to fetch help, but it’s only a fever, Merlin can tell him how to treat a fever, there are herbs …
“It isn’t a fever.”
Merlin doesn’t care about that, he’s burning, it doesn’t matter if it’s the sun or illness or if he’s on a pyre, as long as Arthur stays, and he reaches for him with clumsy hands. “Stay, you must stay, don’t leave me.”
And Arthur stays. There’s something resigned in his expression, something wounded, but he doesn’t bat Merlin’s hands away, and he gives him cool water to drink.
“You don’t even know what you need,” says Arthur helplessly. He’s too far to reach, and Merlin squirms on his makeshift pallet. He’s uncoordinated, his magic flaring under his skin but untouchable. Maybe he’s dying, but he doesn’t know what did it, he doesn’t know …
“I need you.”
Arthur looks away.
The heat is everywhere now, crawling inside him. Maybe he’ll burn to dust and blow away.
“I thought maybe you’d be able to heal yourself, that you …” It’s dark. Arthur started a fire, but Merlin doesn’t know why. The world is burning, and Arthur isn’t making sense, nothing makes sense but the fever and the chasm inside him, and he doesn’t know what he needs, but Arthur has it, he must have it, Arthur is the only anchor he has.
“Please.” Arthur hasn’t touched him in hours. Years.
The world shifts, and Arthur’s face is over his again. Merlin wraps his hands in Arthur’s shirt so he can’t go. “Listen to me. You drank from a cursed spring, and it’s made you need …” Arthur’s face twists. “If I don’t fuck you, you’ll die. Do you understand me?”
That makes the heat tighten, makes Merlin whine like an animal, but he nods, because oh, he can feel it now, he knows what that ache is. “Please.” It’s the only word he has in him.
“Do you want me to do it? I will.”
Arthur looks as though he expects Merlin to choose to die, but Merlin has wanted this for centuries. He’s wanted it since the world began. And he must say so, because Arthur’s expression shutters before he nods.
Arthur undresses him and rolls him over, naked on his knees and elbows, his legs spread. Now that Arthur has decided, his hands never leave Merlin’s skin for long, leaving a path of blessed cool.
He must have checked Merlin’s bag, because he’s found some sort of slick, and soon enough he’s pressing a finger at Merlin’s entrance, spreading it around until the muscle gives and lets him in. Merlin groans high, pushing for more pressure, more everything.
Arthur is steady. He doesn’t fuss, now that he’s decided, he just opens Merlin with one finger, a second, a third, moving and twisting until Merlin feels like iron on a forge, molten and molded into what Arthur needs.
“Are you ready?” Arthur asks, and Merlin can only hope that his whine suffices as an answer.
It might hurt, if Merlin weren’t beyond hurt. Arthur isn’t gentle with him, but Merlin doesn’t want his gentleness. The moment Arthur starts fucking him, it’s all Merlin ever wants in the world. He’s still burning, but now he sees a way clear to the flames going out, and it’s Arthur, everything is Arthur, firm hands on his hips, body aligned with his own, wrecked voice in his ear, gasping out “Merlin, I’m sorry, you’re so good—”
Merlin screams when he comes, he’s in flames, he’s—
There’s cool water on his face, and Merlin wakes up to Arthur watching him again. His whole body smarts and stings, but his head is clear. “Thank you.” He’s unexpectedly hoarse.
Arthur shakes his head and pulls away, and Merlin so badly wants the excuse to ask for his touch again, but he doesn’t have it anymore. “There aren’t any thanks needed.” His back is to Merlin when he speaks again. “I would have done it even if you’d said you would rather die. I needed—” He stops, and when he speaks again it’s hard and clipped. “Get dressed. We ride for Camelot as soon as we can.”
Merlin has never felt so cold in his life.