Oral, comeplay. Kind of short WHOOPS but I don't care, here, have this.
Kakashi's fairly certain he shouldn't be getting so much out of this, and maybe in the morning he'll feel bad about it, but right now nothing else matters. His entire world has been narrowed down to the spot of space and time in which Yamato is on his knees between Kakashi's legs with Kakashi's dick in his mouth, making the most obscene noises ever known to mankind, fully clothed and in his uniform while Kakashi is completely naked, and every single detail of this is so important because Yamato is leaving on a mission soon and Kakashi needs to memorize this down to the most minute element so that when he recalls it later with his hand on his cock he won't forget any of it.
This feels incredible – Yamato knows all of his buttons by now, and his tongue is pressing every single one, humming as his lips hover just below the edge of the head of Kakashi's dick, ever so slightly running his teeth over that edge, pressing his tongue against the slit, and Kakashi grips the armrests of the chair he's in and tries hard not to buck his hips into Yamato's mouth, not wanting to hurt him.
Yamato, however, seems to know exactly what it is that Kakashi wants, because in the next instant he's taken Kakashi almost all the way in, his nose buried in Kakashi's pubic hair and his lips wrapped around the very base. He moans and swallows, and the feeling of it all around him strips the last of Kakashi's resolve away as his back arches and his hips snap towards Yamato's face. Yamato chokes, but even that feels perfect, and Kakashi feels awful for it, but at the same time the obscene little moan that Yamato lets out the moment he has air again makes him think that maybe it's not as bad as he thought.
Kakashi reaches out and puts a hand in Yamato's hair, though he has to restrain himself from pushing his head down further onto Kakashi's dick. Yamato's hair is short and coarse but it's also the perfect length for Kakashi to run his fingers through, which is all he can do to distract himself enough to make this last just that little bit longer, because right now he wishes that this would never end.
Yamato takes him deep again two or three times, moaning throughout the whole thing as if having Kakashi's dick in his mouth is the best thing he could imagine (which it certainly is for Kakashi, but he figures Yamato must have a slightly different perspective on it). The tension builds in Kakashi's stomach, mounting higher and higher until, just as Kakashi is certain he's about to tip over, Yamato pulls off with a popping noise and looks up at Kakashi through long eyelashes. His lips are bright red and his cheeks are flushed, his hair mussed from Kakashi's fingers and his pupils blown wide. Kakashi can barely look at him – it's obscene, how beautiful he looks right now.
Then Yamato wraps a hand around Kakashi's dick and starts to pump. He mouths at the base of it, draws his tongue over the head in long, flat strokes, and then backs off and just plays with his hand. Kakashi is openly moaning now, unable to keep the sound inside his mouth as Yamato brings him closer and closer. He grips tight to the armrest with the hand that isn't in Yamato's hair and then—
He comes hard – harder than he has in a while – and the relief of it, the spectacular moment of orgasm, is so completely perfect that he would never believe it had happened if he hadn't experienced it himself. He's left breathing hard, panting even, and his grip on the armrest doesn't relax for a long time. He just lays there, eyes closed, one hand still pushing fingers through Yamato's hair, and tries to catch his breath.
Finally, though, the sound of a zipper catches his attention, and when he finally opens his eyes, he's met with a scene that's so much more obscene than anything else that they've done yet. Yamato is half bent over his own cock, holding it tightly in his hand as he jacks himself off – but that's not the part that really sticks out. What makes the scene all the more appealing is the fact that Yamato's face is covered in Kakashi's come – that he's jacking himself off while Kakashi's come drips down onto his dick, and Kakashi can't believe how incredible of a sight that is.
Biting down hard on his lip, Yamato reaches blindly with the hand that isn't wrapped around his own dick to try to find the box of tissues, which Kakashi hurriedly hands to him and Yamato gratefully takes with just a quiet moan of thanks before he returns to his work. Then, finally, after what seems like ages, he comes with a groan and his head slumps forward onto Kakashi's knee while he rides out his orgasm.
After Yamato comes, they're both silent, no noise except the sound of them both breathing hard while they recover. Kakashi still has his hand in Yamato's hair, and he rubs gentle circles into his scalp while they sit there.
Yamato looks up at Kakashi after a while and smiles, and Kakashi would swear that if he was a teenager, the response to seeing Yamato with Kakashi's come still all over his face would be instantaneous. But he's older now, and things don't happen that face, so he just gently tugs on Yamato's hair and murmurs, "Come here and let me clean that up."
Yamato gets up on his knees and Kakashi leans forward, taking his face between his hands and leaning forward to kiss him. The kiss is soft and gentle, but there's also the bitter, salty taste of Kakashi on Yamato's lips. He holds Yamato's face very carefully between his hands as he licks the taste of himself away from Yamato's lips, his chin, his forehead and cheeks, the small speck on the side of his nose underneath his right eye. It tastes strange and off but Kakashi erases all of it from Yamato's face, and afterwards he kisses Yamato again and obviously he must have done something right during all this time of doing nothing, because Yamato slides a hand into his hair and pulls him deeper into the kiss.
They break it silently, and then they just sit there for a while, foreheads pressed against each other and breathing each other's breath.