Merlin is fucking gorgeous like this: splayed out across the bed with Arthur's cock deep inside him and his neckerchief wrapped so tightly about his neck that his whole body is pulled bow-taut with its need for air. His fingers twitch against the sheets, the muscles no longer obeying his brain's command, and suffocation battles with intense pleasure.
The first time they did this was right after Arthur had a heated fight with his father, Merlin being at the center of the argument. When Arthur had returned to his room in a rage, Merlin had been waiting there for him, unafraid. Almost daring. That had been the first time. Rough, over the table and with too little preparation, something Arthur had felt sick over until Merlin had reminded him that it would have taken only a thought to change that.
The next time had been the night after Uther had passed away, Morgana's true intentions had been exposed and the weight of the Camelot's need had come to rest fully upon Arthur's shoulders. It had been nearly six months since the first time, something Merlin had later bemoaned and that marked the true beginning of things. Now barely a week passes without Merlin pressing Arthur against the nearest surface, eyes black-gold with desire.
Arthur loosens his grip enough for Merlin to drag in a much-needed breath, but the moment the lean body begins to relax, Arthur's fingers pull the neckerchief tight once more. He can see the satisfaction, the desire, the love in Merlin's gaze. Can feel it flowing through him as he thrusts in deep, Merlin's body so tight and hot and—
"Yes," Merlin hisses, wasting precious breath. His arms are heavy as he lifts them to pull Arthur closer.
Arthur flexes his hand, letting the material go loose before fisting it again, teasing Merlin with the prospect of air as he continues to drive himself deeper and faster and harder. With every thrust of his hips, Merlin's lifted higher and higher, his lips drawing tight as the lack of oxygen begins to take its toll. Arthur can tell by the tension that lines Merlin's eyes that he is close, and Arthur reaches down between them to grip the base of Merlin's cock tightly. He smirks at the wild look in Merlin's eyes, then drives himself in deep one final time, coming hard as he lets go completely of the neckerchief.
Arthur nearly collapses right then; the muscles in his arms and legs are melting in the post-orgasm heat that always leaves him feeling languid and relaxed. It is a fight for him to pull back, to slide down Merlin's body until his mouth is level with Merlin's cock, but as his lips closed around it, he can hear Merlin chanting and he knows that it is worth the extra effort.
Arthur looses his hold on Merlin's cock and not a second later his mouth is being flooded by Merlin's release. He fights the his now-natural instinct to swallow, letting it gather in his mouth until Merlin is done, his hips stilling and his body going limp. Then Arthur moves up, lays himself down along Merlin's side and presses his mouth to Merlin's.
When the full lips part beneath his, Arthur opens his own and lets Merlin's seed pass between them, his tongue chasing the remnants into the warm, wet mouth. He can taste everything, and it is thrilling and wonderful and absolutely filthy. Arthur loves it.
As their heart-rates slow to something not akin to those of terrified rabbits, Arthur finally reaches for the bowl of water and cloth they had smartly prepared beforehand. He cleans them both up and tucks them under the blanket. Pulling Merlin's loose-limbed body into his arms, Arthur slowly traces his fingers over the already darkening marks that ring the pale, slender throat. Come morning they will be full-fledged bruises, marks of Arthur's claim over Merlin, Camelot's Court Sorcerer.
"Next time—" Arthur begins, breaking off he yawns hard enough to make his jaw pop. "Next time we should use the one that silly countess gave you as a Beltane gift."
"Mm." Merlin curls in tight around Arthur, eyes already slipping shut. "Or the belt King Rience's eldest son gave you for keeping me in line."
Arthur chuckles. "Yes, or—"
And Arthur does just that, slipping easily into sleep where he dreams of long, pale limbs, dark, wavy hair and eyes that burn gold at his command.