Spock pays when they go out. He lets Jim pick their locations until he cannot bear the loud noise or the frantic energy of places Jim frequents, and then he makes him accompany him to a quiet, delicately and tastefully gorgeous location, where Jim lets him order because, as he says, "I have no idea what the fuck that even means."
Jim Kirk is a loud, abrasive, brilliant Human.
He slouches outside Spock's classrooms, comes in and puts his PADD (technically Spock's, and technically testing devices, but Spock is surprisingly unconcerned with technicalities where Jim Kirk is concerned) on the desk and complains about specious arguments, about idiocy in tactics, flaws in the prime directive. He paces the length of Spock's apartment, taps out idle patterns on walls as he walks through them. He is incapable of stillness.
"I'm just saying, the argument is invalid because the solution is a null integer." Jim is now leaning against the island in Spock's apartment, turning over his beer, a frown etched on his face. "And it wouldn't be annoying if it wasn't in text books, you know? But nobody thought to challenge it and—"
The most effective way of silencing Jim Kirk is to cover his lips with Spock's, to press him into a wall or against the desk, lick into his mouth until Jim is clinging to him, never subdued, but acquiescent.
It is not that Spock does not enjoy Jim's intelligence. He does. Perhaps too much, but it is impossible not to be utterly drawn to the magnetism of Jim Kirk.
Spock finds himself discussing him with Christopher Pike, with his mother, even with his father.
He also finds himself in low lit, smoky rooms, watching Jim laughingly sing about an American woman, and how she should let him be; get away. Spock is not given to metaphor, but the fact that planets are given feminine pronouns is not lost on him.
Later that night, with Jim's legs wrapped around his hips, Jim sings in a gravelly voice in Spock's ear, tight around Spock's cock, laughing, laughing, laughing.
Spock thinks this is how it should be, legs tangled and sheets twisted, Jim sleeping in the dark of Spock's room, in Spock's bed.
Jim yawning in Spock's kitchen, coaxing food out of the replicator in his boxers, cajoling coworkers into taking shifts or giving him an extra, wheedling with employers or charming friends.
He will someday be more: he is, now, a writhing mass of wasted potential, and Spock wants for him to be more: wants Jim to want to be more.
But selfishly, as he makes himself tea and Jim finishes his third cup of coffee, he thinks that when Jim does reach his potential, this will be lost. Jim will no longer be exclusively his. He will no longer.
Ten Years Later:
"That is your seventh cup of coffee."
"I keep brewing it to get rid of the smell of that shit."
"Vulcan tea is—"
"Gross, I know," Jim agrees, and sulks into his coffee. His hair is a wreck, and it is nearly noon. He has only just made an appearance.
"It is not a food—"
"You know, we've been having this fight for ten years," Jim reflects, checking over the day's news and scowling at what he doesn't like in a manner much like Dr. McCoy's. "I think the sheer virtue of the fact that you haven't won means I have."
"This argument is zero-sum?" Spock inquires, wry.
Jim grins. "Um, yes?"
"I had not previously been aware," Spock admits, and kisses Jim. They both, in their own way, make a face at the taste of the other's mouth.
"The magic is gone," Jim sighs, and as he goes to shower and brush his teeth, Spock begins cooking a meal he will spend forty minutes coercing Jim into eating. He should visit his father, and Jim should check in with Mr. Scott, but they have two weeks, and none of the crew has joined them at the house.
The rest can wait.
"I have no idea what the fuck that even is," Jim informs him, looking at the food over his shoulder.
Spock sighs, and Jim withdraws, coaxing more coffee out of the replicator, cajoling Mr. Scott into modifying the nacelles in a way which is not particularly legal (though it is a gray area, by sheer dint of the fact that no one else has come up with the modification yet), bargaining with Admiral Pike about their next mission.
His pants hang low on his hips, and Spock's fingerprints are pressed there in purples and reds.
Spock drinks his tea and finishes the meal, and Jim eyes it suspiciously.
"So I was thinking," Jim begins, speaking the phrase that must surely be a prelude to disaster, "that Vulcans would totally dig karaoke."
He has a list of reasons he believes this to be true, complete with footnotes.
Spock mentally begins composing apologies to Vulcan High Command.