He'd fought it at first, mostly because fighting was all James T. Kirk knew how to do.
Fought Bones's easy, gruff friendship to start with. Until he noticed that Bones didn't have a lot of friends, didn't make a lot of effort to make a lot of friends, and then he'd felt kind of (honored) sad for the guy, and given in.
Then he'd fought turning their friendship into something more, because for the first time in his adult life, Jim had something he didn't want to risk ruining with sex. Not even the mind-blowingly awesome sex he just knew they'd have together. What? He's good at predicting these things. He's got a big enough bank of experience to draw on, okay?
He hadn't fought the idea of monogamy. Hadn't needed to. Bones hadn't ever asked for that. It just sorta happened and Jim found he quite liked it after all.
He quite likes this too, although he still pretends to object, every single time. People think Bones doesn't listen, hell, he used to think it too. But Bones listens. Listens hard and listens good. He listens underneath what Jim's saying with his ever running mouth to what lies beneath.
So, yeah. Jim'd always known Bones would be a cuddler.
With anyone else he'd've escaped at the first creep of postcoital arms around him, but this was Bones, so he'd stayed that first time, uncomfortably stiff in all the wrong ways until his friend was deep enough asleep that he could get away. Gone back to his own (cold and empty) bed.
Stayed a while longer the next time. Was maybe even sorta still there when the alarm went off the time after that, and all right, maybe postcoital snuggling wasn't so bad when you were in an actual honest-to-God relationship with the person you were tangled up with.
This is better though.
Cuddled up warm and close under a McCoy family heirloom quilt, gathered up in strong arms that are just holding him, not holding him still, or down, or any of those other things he'd always feared. Bones isn't even paying him any mind, except in the idle way one of his thumbs is stroking patterns into Jim's elbow.
Jim burrows in closer, rests his head against the warm muscle of Bones' shoulder, and listens to the hum of the Enterprise going about her business.
All that time, he was fighting to get here, and he never even knew.