He watches them, watches his naked back, the way his muscles move as he rises and falls above her body, carefully pushing in and out. Her hands caress his shoulders, his chest, his sides, unable to be still, dwelling much like Merlin's hands would love to -- like his thoughts do at all times, helplessly, entranced.
He imagines himself in Gwen's place, beneath Arthur, beneath that strong, golden body, cradled between his lover and the sheets, feeling protected and trusted. Loved. The thought makes him shudder, sends heat coursing through his veins. He can't touch himself, not here, not now. Later, perhaps, when he's alone. Alone, so very alone.
They are gentle this night, can't stop stroking and caressing each other, lips touching lips and skin and lips again. She murmurs his name, takes it into her mouth, whispers it into the skin behind his ear. He calls her Guinevere, always, and so it comes as no surprise that he does this even in the throes of passion, out of breath, lovingly, reverently.
Arthur's hand slowly moves down Gwen's body and for a moment, Merlin has breasts, feels what Gwen is feeling, feels Arthur's fingers on his flesh, his skin so sensitive and tight. He gasps, inaudibly, hands moving to his chest, reaching for hands that aren't there, for caresses that aren't his to feel, and yet he is feeling them, and he stares down at his hands and thinks of his magic and surely he didn't -- because he would know, wouldn't he? Except he sometimes cast spells without knowing before, and now . . . and now Arthur is kissing his throat, and he is tilting his head to the side, granting his husband better access and the feelings, oh, the feelings, they are too much, too consuming, they will wash over him, destroy him and leave nothing but ruins in their wake, they will, they will --
Gwen comes and he goes, goes high -- so very high -- and where Gwen ends he begins, and as Arthur pushes into her/his/her wetness, Merlin's toes curl upwards and he sinks back against the wall, invisible hands searching for support behind his back. Finding none, he slides down,
down until he hits the ground and lies there, shuddering, unable to catch his breath.
"Are you alright?" someone asks, and Merlin nearly answers, opens his mouth to tell them no, he is not, how could he ever be? But yes, he truly is, he has never been better, will never be better, except what he did was bad and not good, so he can only become better, can he not?
Then he hears Gwen's breathless voice. "I am fine."
And he knows, feared for some time but now knows for certain that not even Arthur's words are meant for him now, because everything he has is meant for Gwen, and that is the way it always will be between them from now on. The way it was never meant to be. Surely destiny never meant for things to be this way?
He listens to Gwen's giggle, hears Arthur's groan as she coaxes him onto his side and then onto his back. The Queen rolls on top of her husband, stares down at him with love in her eyes and Merlin fleetingly wonders if the spell stopped working because he doesn't feel a thing, but then Arthur is gazing up at him and Merlin feels, oh, he feels, but it is nothing but despair, because the love in those eyes is not meant for him, and it is slowly but surely destroying him.
Gwen is moving, steadily, up and down and back and forth, her powerful legs doing most of the work even as her hands trail over Arthur's chest, circling his nipples and teasing sensitive skin. Merlin is watching them from a distance and through Gwen's eyes and it makes his head hurt and his heart ache and he wants it to stop, but he doesn't know how to end it. The switching viewpoints are making him dizzy and he can think of nothing but Arthur and Gwen, can be nothing but Arthur and Gwen, and something inside him breaks when he realizes they aren't thinking of him right now, will only ever be able to offer him friendship.
And just like that, a tingling sensations spreads through his body (or is it Gwen's?), his veins (or are they Gwen's?), his very core . . . and it is his. He's catapulted back into his own body, lands with a cry that everyone in the room can hear but no one listens to, and as Arthur cries Guinevere, Merlin closes his eyes and lets the sound wash over him, destroy him --
And leave nothing but ruins in its wake.