Things Unspoken
The crew of the Enterprise notices something different between their captain and first officer, but they won't ever tell.
They started noticing when the touching began.
Staring wasn't uncommon between the captain and commander anymore. Even before they were captain and first officer, when they were at each other's throats, there was a real danger of physical harm if you tried to get between the two of them during a staring match.
It was one of the unspoken rules aboard the Enterprise that you didn't talk about the captain and first officer together in one sentence. At least, not in front of them. Mess hall and crew quarters were fair game, and occasionally the medbay when Dr. McCoy was on duty. To do it seemed like tempting fate in a way, giving karma an extra nudge over the fence of reality. So they whispered about it, and thought about it, and said nothing to the pair in question.
Sulu was the first to notice. He was turning in his seat to offer Kirk the time of arrival to their next destination, when he saw Spock standing behind the command chair. That in itself wasn't too strange, but his hands were unmistakably placed on the captain's shoulders, absently kneading in a light massage.
Sulu gawked, his words backflipping back down his throat. Kirk noticed him then, and gave a slight shrug, more of a twitch than an actual motion, and Spock's hands slipped back behind his back. "Mr. Sulu?" and that was that.
A brushing of shoulders in the corridor that lasted longer than necessary, a casual pat on the back, a light brush of fingers passing over PADDS. Little things like that, but lots of little things added up into a big thing, and a big enough thing was enough to be reality. Further evidence was dished up in clandestine meetings
"About time," Scotty grunted, digging beneath his clutter of a desk and producing a dusty bottle of scotch. "I'll drink to that!" Celebratory drinks were passed around, and the bridge crew departed to their quarters that night with a strange air of bemusement and relief. God knows the two of them had danced about each other long enough.
...
"Do you think they've noticed?" Jim murmured, his lips moving against the underside of Spock's throat. He could almost taste his pulse point, feel the fluttering of his heartbeat just beneath the skin. He breathed in deeply, that minty scent that was so exclusively Spock's giving him a heady rush.
Spock considered for a moment, his own face buried in the top of Jim's head, and sighed into his hair. "I doubt it, Jim."
"You sure?" Jim asked dubiously. "You've been kind of, I don't know, handsy lately. Not," he added, "that I'm complaining." And he proved his point by grabbing Spock's ass, pulling him forward playfully.
Spock loosed a grunt of surprise that turned into a growl, and fingers tangled into the short hair at the back of Jim's head, catching his mouth in a hard kiss. He then proceeded to show Jim just how handsy he could get.
Really, Jim couldn't complain at all.