Clark wakes up sometimes with his throat constricted, drawn so tightly closed that it actually *hurts* to try to breathe. Lex places a hand on his back, tells him to relax and not struggle so damn much; his voice is rough with sleep, a little edgy with a panic that makes Clark realize Lex is out of his depth, too.

He wants to say: so many things, but none of them make it past this knot deep inside of him, and so he shakes his head when Lex barks out an order into the telephone; a doctor questioning and probing and *discovering* is the last thing he needs.

Lex is all tight lips and guarded eyes, and this new expression, this wariness, has become too familiar for Clark to just shrug it off as nothing. But he can’t say what he wants to, can’t do what he’d like to, and so instead he takes a breath, then another, and another, and when he is finally drawing air in with ease, Lex sinks back into the bed, not complaining, but not entirely happy, either.

“What’s going on, Clark?” he asks finally, and Clark shrugs, says it’s just a dream, but that he can’t quite remember the details of it.

And something tightens inside of him, twists a little harder with every lie, and he smiles at Lex to cover the ache of it, kisses him. Slides his tongue into Lex’s mouth, toying, teasing, just as he’s been taught, and Lex, Lex makes this *noise* in the back of his throat - part pleasure, part frustration, and it’s enough to make Clark lick at that smooth, pale neck in hopes of extracting that sound again. It slips out from Lex’s parted lips, and Clark wants to bite his neck, bite through to discover what that noise *really* is. And this is it, right here: what he can’t tell Lex, why he can’t say *anything*, because he knows that if he does, it’ll be exactly like the dream.

So he slides his hand beneath the covers, slicks his hand with lube from the nightstand and works Lex’s cock, harder, with more desperation than he would ordinarily have, and when Lex comes, face beautiful and white as marble in the moonlight, Clark knows he is saved for another day.

He sleeps, eventually, and in his dreams, he is able to say everything he cannot when he is awake. He tells Lex everything, and Lex -

Lex stares at him, watches him as though he’s a stranger, as though a monster has crawled beneath his skin and is masquerading his Clark-body around for all to see, and he says,

“What are you?”

And when Clark wakes up, he can’t breathe.