Disclaimer: Not mine. Summary is from Star Trek: The Original Series.

A/N: Sometimes, when you're bored you have to write a Kirk x Spock PWP drabble.

People might wonder what Jim sees in Spock, but there are too many things to name.

He's intelligent. So intelligent that Jim, with his quick mind, the mind that beat the Kobiyashi Maru, the mind that survived Tarsus IV, the mind that completed the Academy expedited and top of his class – pales in comparison to what Spock can think in a single moment. It's magic watching him think and when 100% of that mind is focused on a single person – well, that's magic, too.

Jim loves the things that no one else can touch, the things they want to know more of, the things they imagine. He is the only one who knows the sensitive swoop of Spock's ear, the way the slightest touch of it can make him writhe. He loves to trail his fingers, counting, down the ribs, slightly ticklish, though Spock would vehemently deny it. When he blew cool hair on nipples, then covered them with his hot mouth, he could make Spock arch off the bed like a wave. He loves the way those legs fall open so wantonly when Jim trails his fingertips up and down long thighs. He loves the feel of sinking into that hot, wet heat, as tight as any vice. The feel of it is like what he imagines Heaven is like – it is warm and welcoming and feels like… like coming home.

And it makes Spock make the most unintelligent sounds he's ever heard. Sounds that no one but him will ever get to hear him make. Whining and keening and high, breathy sounds. If he had had a hundred years to imagine what Spock would sound like when someone was pounding into him, buried to the hilt in him, he never would have been able to do it justice.

But mostly… mostly he loves the things that people don't even think about that he knows are true. That Jim is the only person who can see how emotional Spock really is, that he is soft on the inside, but no one is allowed to see that side of him but Jim. His eyes sparkle with laughter and his lips quirk with amusement. Jim can sense what he is feeling from just a glance at his face, and no one is that close to him, or ever was. Not Uhura, or T'Pring, or his father. Those looks are just for Jim.

Spock loves Jim's fingertips. Yes, there are many reasons. The way they feel when they dance across his skin, the way they feel wrapped around him or deep inside him. Especially that. But really, mostly, he loves the way the sensitive finger pads feel against Spock's own. They are calloused and rough and they grate against his as sinfully as any kiss, the fervor of his mind dancing just beyond them. It never failed to make Spock blush green to the tips of his ears.

He loves the blueness of Jim's eyes, as bright and clear as the sky. He loves to watch the pupils blow wide with pleasure until the blue is a mere sliver of color while he watches Spock sink slowly down on his length. He loves watching that chiseled jaw clench with the effort to not simply flip them over and take him, because he loves what Spock is doing. And Spock loves it when he can make Jim lose it, when he clenches his inner muscles just so and in a surge of frenzied motion Spock finds himself on his back.

What Spock loves above all else though, what he would kill for, kill to protect, is Jim's mind. It is open and bright and the most perfect thing that Spock has ever touched that sometimes he must force himself not to. One touch and he comes undone, release spiraling high and ragged before they've even touched one another. It makes him shiver just to think of reaching out to brush those thoughts wantneedminelovelovehimmineyespleasemine –

All his, his, mine. Perfect.