Clark lets out a disbelieving little snort, cut off when Bruce lowers his head and nips at his thigh. His muscles tense under Bruce's hands, and that just makes Bruce smirk against his skin. When he glances up through his lashes, Clark's worrying his lower lip, his eyes somehow full of both lust and an almost puppy-like kind of pleading. Bruce watches the steady rise and fall of Clark's chest, the almost rhythmic way in which his arms flex and relax as he tries not to shift in his bonds, such as they are.
If Bruce were a different man—or perhaps just a younger one, a more foolish one—he'd pull back and get a picture of this exact moment: Superman, gloriously naked and splayed across his bed, face and chest flushed and eyes dark with desire, hard and wanting and yet not doing a damn thing about it. But he knows how easy and how cruelly such things can leak and spread, and he isn't prepared to do that to Clark. (Ostensibly, because of what it could do to the security Clark's civilian identity, still a little tenuous in the wake of his resurrection. And, perhaps, because he knows he couldn't bear how such an infringement would cause Clark to suffer, and certainly couldn't shoulder the guilt that would come with it.)
Instead, he shifts back until he's between Clark's ankles and sits up on his own heels, raking his eyes across Clark's incredible, flawless body, and burns the moment into his memory, a snapshot for him and him alone, to be pulled out of his mental filing cabinet whenever necessary.
Clark swallows, his Adam's apple bobbing tantalizingly. Fitting, Bruce thinks, as he gives in to temptation, crawling back up his body to scrape his teeth over the impossibly soft skin of Clark's throat. Clark lets out a quiet, shaking breath, his body shivering beneath Bruce's weight. The mattress shifts as Clark draws up his legs, hooking a knee over Bruce's hip, which just will not do. Bruce's smile then is just as sharp as ever, as he slips a hand under Clark's knee and coaxes him back down onto the bed.
"Behave," Bruce commands, "unless you want me to tie your legs down too."
Clark gives a sound perilously close to an actual whimper then, which is... intriguing, and something to be examined later. For now, Clark obeys, though the way he spreads his legs just a hair's breadth wider than before is more than a little telling. Bruce kisses him on the mouth, a reward, and resumes his journey down Clark's body.
His legs, too, are dusted with dark hair, all the way from his upper thighs down to his ankles, ever so slightly rough against Bruce's lips and cheek. On the surface, Clark is so ordinary—except no, no, there's not a world in which Clark Kent could ever be considered ordinary—and so painfully human. Yet beneath all of that, not a single imperfection; not so much as a mole, let alone a scar, the perfect smoothness of his unblemished skin belying his invulnerability and fundamentally alien origins.
Had Bruce not spent the better part of a year cataloging all of the ways in which the Superman was wholly distant and other from humanity, he might have a hard time wrapping his head around the notion. Had he not spent the last several months incidentally discovering all the ways in which Clark was no different from the rest of them (he laughs at videos of penguins falling over until he cries; he drinks coffee with a frankly heretical amount of cream and sugar; he drools on the pillow when he sleeps and clings when he has bad dreams—) then he might be terrified. Instead, he finds himself awestruck, marveling at the impossible man laid out before him.
Some of that awe must be showing on his face, or else some unaccounted-for shift in his autonomic responses. (He remembers when that used to terrify him too, the sheer depth to which Clark could invade his privacy just by listening for his heartbeat, or smelling his hormonal shifts—and it's still unsettling, sometimes, but at the same time, there's a reassurance to be found in the knowledge that the man who can find him in a second from halfway across the world simply by listening for his heartbeat loves is inexplicably fond of him.) "Penny for your thoughts?" asks Clark, sounding much less casual than he probably thinks he does.
Bruce doesn't reply for a moment, instead taking Clark's ankle in his hands and kissing up the arch of his foot. It's something of a testament to Bruce's own resolve that this is the first time he's actually gone so far as to kiss Clark's feet, as prevalent as that particular fantasy tends to be in his more pleasant dreams. What it would be like, he finds himself wondering, to prostrate himself before this quite literally unearthly creature, to give himself over and surrender wholly and utterly to his will? Would Clark even accept that kind of devotion? As willing as he is to lie back and receive the worship Bruce finds himself performing now, Bruce can't quite imagine him having much lasting patience for a worshipper who had once put the proverbial nails into his hands—or, at the very least, forged the hammer that drove them home.
Few things, Bruce finds, ruin the mood quite like Evangelical guilt. Internally chastising himself, and endlessly glad (as always) that Clark's powers don't include any sort of actual mind-reading, he lowers Clark's foot back onto the mattress and strokes idle circles into his calf with his thumb. "You're a goddamn miracle," he says softly.
Clark has a strange talent for cracking half-shy little smiles at the most inappropriate times, ducking his head and dimpling in a way that makes Bruce's heart twist almost painfully, and it is far too timid and endearing for a man bound to and spread wide across Bruce's bed. "I'll bet you say that to all the boys," Clark says, teeth teasing at his lower lip, which is completely unacceptable. Bruce has to put a stop to it, and so stretches up the length of Clark's body to kiss him breathless.
Also unacceptable is the shaky little moan that passes his lips into Bruce's mouth, the way he tilts up his hips, the way he whispers Bruce and please with a soft, trembling gasp as punctuation. Were Clark anyone else, Bruce would think it's specifically calculated to crack at his resolve, but here, in private with all the walls torn down (or, at least, all of Clark's), he's only ever been earnest to a fault. He's given Bruce no reason to think there might be any guile now.
Still, it's not going to work. Bruce has every intention of doing this right.
"Only the ones who've come back from the dead," Bruce deadpans, lowering himself to brush his lips over Clark's throat, feel his pulse under his mouth—and then the low vibration of his laughter.
"Right, how silly of me," Clark says, breathless, tilting his head away to give Bruce more room to explore.
There's a day's worth of stubble scattered along Clark's jawline, the underside of his chin, rough against Bruce's lips. Bruce kisses every inch he can reach, reveling in those little catches of Clark's breath and the way he shifts beneath Bruce's touch.
When Bruce settles against Clark properly, knees framing his hips, Clark jerks up, his cock pressing up against Bruce's stomach for just a fraction of a second. That draws a long, low moan from Clark's throat, another pleading: "Bruce..." His eyes are simultaneously dark with lust and almost pitiful in their pleading—and Bruce can be cruel, he can be utterly merciless, but when Clark has been behaving himself so well thus far...
Setting aside a brief moment to regret that it would take time he's not currently willing to spend to prepare Clark for a more in-depth form of veneration, so to speak—and how would Clark take that, he wonders, Bruce undoing the knots at his wrists, turning him over and pressing his mouth onto him, into him, worshiping with his tongue and hands—Bruce settles back down between Clark's knees. Now's as good a time as any, so he kisses a slow, deliberate path up Clark's inner thigh, not bothering to hide a smirk at how the muscle under his palms tenses as he draws closer to Clark's cock.
"You have," Clark says, "no room to talk about how long I take, you know."