Kakashi is perched comfortably on the edge of their sofa when they come out, unwinding the wrappings from his legs; his vest and gloves are already laid carelessly aside and he left his sandals by the door when he came in. Yamato is a little irked at his senpai's complacent confidence—clearly he knew Yamato couldn't turn him down—but at the same time it's one of the things that made him so attractive all those years ago and it still holds some sway over Yamato's hormones now.
Smug looks good on Kakashi; it's an undeniable truth and Yamato accepts it.
Kakashi glances up as he finishes with the wraps, taking in their faces. "So we're doing this, yes?"
"Yes." At least Yamato's voice comes out steady. He's still so off-balance, excited yet anxious, doubting the wisdom of his decision despite himself.
"Good." Kakashi strips off his shirt and casts it aside, then levels a look at them both. "Are we waiting for anything in particular?"
"I—er." Whatever his feelings, it is entirely too awkward standing here with Sai attentive at his elbow and Kakashi casually stripping with that expectant look on his unmasked face. He knows Kakashi will probably tease, but he asks anyway. "So—um. How do we start?"
Kakashi surprises him with a straightforward, serious answer. "Let me see the two of you kiss."
Yamato blinks, and his mouth opens slightly on what would probably have been some degree of objection—I'm not an exhibitionist; you didn't say anything about watching—even as an unexpected little thrill jolts through him at the possibility that Kakashi would be turned on by seeing him with Sai, but Sai has stepped around and reached up to tangle fingers in the hair behind his ear before Yamato can quite keep pace and then Sai's mouth is slanted up against his, Sai's tongue unfurling between his lips. Yamato tries to ignore the fact that Kakashi's watching them, tries not to feel the way his ears burn at the thought, grasps Sai gently by the back of the neck and kisses him like they're alone in their bedroom. It's easy enough to do; Sai kissing him first without seeking any kind of permission is still a thrill no matter how much more frequently Sai does it these days. It makes it easier to forget his anxieties and lose himself in that little jolt of excitement, to slip his arm around Sai's waist and pull him close and kiss him harder, deeper, until at last he draws back to catch his breath.
Kakashi moves in then, and his expression is unexpectedly hungry and a little bit wistful, a combination so odd that Yamato wonders if he's maybe better off not knowing what's going through his senpai's mind. Sai glances at both of them and steps back; Kakashi gives him a faint nod, then grasps the hem of Yamato's shirt, peels it up Yamato's body and off over his head. Yamato cooperates, right back to feeling awkward again as he brings his bared arms down, not sure quite what to do next.
Kakashi puts a hand on his shoulder and draws him in before he can ask anything, though, sets a thumb lightly under his jaw to tilt it up and tips his own head down. Yamato can't help shivering as Kakashi kisses him again, and—oh—
This is not the gentle introductory kiss that Kakashi offered at the outset; this is Kakashi kissing him heavy and hard, coaxing his mouth open like it's nothing and delving in with his tongue, Kakashi touching his face and running light fingertips down his neck and back up to slide under his hair, curl around the base of his skull, cradle his head in both hands while stealing his breath away, and Yamato is reeling. It's not right that he can be so completely overwhelmed by just a kiss, but there is more than ten years' worth of sublimated teenage longing simmering deep inside him that is finally freed, rising and heating and boiling to the surface. He's feeling giddy and horny and a little delirious; Kakashi's a very decent kisser and suddenly its like he's sixteen all over again. He's got a hand gripping Kakashi's hip and one hooked in the loop where Kakashi's tool pouch attaches; Kakashi's chest is warm against his and Kakashi's hands in his hair feel so good and it's not until they break apart a long moment later that he wonders where Sai is supposed to fit.
But Sai is close behind him now, has started pressing soft kisses to the skin between his shoulder blades, is sliding gentle hands between him and Kakashi to stroke the bare skin of his stomach, to toy with the trail of hair that leads down. Sai has discarded his own shirt in the interim, and his skin is warm against Yamato's back.
"Take his pants off for me, Sai."
The words are low and uttered almost directly into his mouth and Yamato never imagined hearing Kakashi tell someone else to undress him would be such a turn-on, but Sai's slender fingers moving to open his fly, to obey, is somehow even more so. It helps nothing that Sai is being overly-sensual about it, smoothing his hands over Yamato's hips to push the pants down instead of pulling on them directly, running his lips over Yamato's buttocks and down the backs of his thighs while smoothing both hands down either side of each leg from thigh to ankle. Kakashi is kissing him slow and heavy all the while and Sai's fingertips gliding over the inside of his thigh make him shudder. Sai carefully draws Yamato's bare feet out of the pants one after the other and then rises to stand again, hands traveling back up Yamato's legs to grip him gently by the hips.
"Thank you," Kakashi says then, to Sai, before assaulting Yamato's mouth with short, searing kisses that make him genuinely weak in the knees, god help him. It's not right that his senpai can still have this kind of power over him, can make him react so completely, but there's nothing he can do for it and when Sai presses up against his back again, skin against skin, Yamato shudders. Sai's lips are running over one shoulder and across to the other and Sai's hands are doing that thing again where his fingertips glide down the front of Yamato's bare legs and drag lightly back up the inside of his thighs, a touch that would make him laugh for it's ticklishness if it wasn't so damned erotic. As it is, he's making ridiculously needy little noises into Kakashi's mouth and his dick is rock-hard, aching, and then Sai's hands smooth up his pelvis and take hold of him, gliding one after the other down his length again and again.
That earns a proper gasping groan, and Kakashi withdraws from the kiss and steps back as much as Yamato's grip on his pants will allow, hands falling loose at his sides. His gaze flicks down to where Sai is stroking Yamato and his mouth curves up at one corner, approving, and Yamato can feel his ears turning red at the blatant appraisal. He lets go of Kakashi, puts his hands over Sai's to stop him because it's...it's embarrassing to have Kakashi smirking at him like that, like it's dirty to let Sai touch him. He doesn't want this to be...sleazy.
Sai stops touching, wraps his arms loosely around Yamato's stomach and presses his cheek to Yamato's back, and Yamato is a little bit jealous that Sai doesn't know how to feel shame for being so demonstrative in front of Kakashi. He doesn't want Sai to feel shame of course, doesn't want to be ashamed himself, or embarrassed, or any of the other things his mind keeps insisting he should be; this isn't going to work if he can't get his head on straight, he knows that, but it's hard to overcome that programming.
"Okay there, Yamato?" Kakashi's voice is light, solicitous, colored by friendly concern, and Yamato takes a deep breath.
"Yeah. Just...it's—I'm not used to you staring at me like something out of those books you read," he says, which is lame and not exactly what he means, but it makes Kakashi laugh.
"I stare so I'll remember," he says, light and dismissive, but his eye is completely serious.
"It's not dirty," Yamato insists, apropos of nothing but unable to help it. "There isn't anything wrong about what we're doing."
Kakashi looks at him quizzically. "Who said there was?"
"...No one." He shifts, aware that he's being a little weird about the whole thing and just overall embarrassed.
"Then don't worry about it," Kakashi returns, but the look in his eye says maybe he gets what Yamato means, and something in his expression shifts slightly—less cocky and lascivious perhaps, more sincere. Whatever it is, it eases Yamato's concern somewhat, and then Sai speaks up against his back.
"Yamato..." One hand slides up to Yamato's chest and the other arm moves closer around Yamato's stomach, a proper embrace. "If you have changed your mind—"
"I haven't." Despite all his awkwardness, that much at least takes no thought.
"Then please try to relax. I...want you to enjoy this." Sai's arms tighten briefly.
Yamato lets out a deep breath, chastised. "Sorry. I am. Or I will. It's just strange—
"You're thinking too much again," Kakashi interjects. "Stop that."
His tone is one that he's always used to lightly goad Yamato into doing what he wants, equal parts dismissive and teasing with a thread of challenge underneath, and Yamato recognizes the subtle manipulation but can't help responding the way he always has.
"Yes, Senpai." Which really means I'll show you I can be just as at-ease about this as you are.
"Do you want to move to the bed?" Kakashi asks then. "Or would we be better off on the living room floor?"
Yamato considers that for a second. "I'm pretty sure the bed will be more comfortable." There should be enough room for them all.
"Perhaps we should finish undressing first," Sai suggests, moving away from him, and Yamato realizes suddenly that he's the only one fully naked at this point; he almost laughs when he finds that he has to quell the ridiculous urge to cup his hands over his vital bits.
"Yes. That's a good idea.