This is from a J prompt (TOS)

“Jim? You going to go to the rec room for a drink with me and Scotty?”

Jim smiled faintly at Bones. He was feeling a little melancholy, truth be told. They were in deep space. Way too far from Earth or anywhere, really, for a shore leave for the holidays. In fact it was unlikely they’d get shore leave any sooner than another three months.

Not that they got to spend the holidays with family often anyway. Jim was used to that, for the most part, even from his days on the Farragut. But at least then he’d been able to keep in touch with his parents. Now they were so far out, communications with Earth or any planet out that way were non-existent.

And maybe that wouldn’t even bother him if the last time he had spoken with his folks it had been revealed his mother wasn’t feeling well. He’d been assured it was nothing to worry about, but they were getting on in years and both had lost some zest for life after Sam and Aurelan’s deaths. Still they had Jim’s nephew to watch over.

Jim would just feel better if he knew his mother had improved. But he wouldn’t get to know that. Not now.

“Well…”

“It’s Christmas Eve, Jim. One drink.”

“One,” Jim agreed. “And then I really need to go to bed. I’m beat.”

It ended up being two drinks, because Bones and Scotty could not or would not be refused, and Jim admitted he might have felt a little more cheerful at the end, especially when Uhura dropped by to croon, “Santa Baby”.

But Jim did refuse the third drink. And made his way back to his quarters.

Rand had put a few festive touches there. Hung some red and green garland. Put up a few silver and gold bulbs. He’d mostly ignored it. But now it just reminded him just now alone he felt.

He went into the bathroom and brushed his teeth and washed his face, his gaze going to the door that led into his first officer’s quarters.

Spock.

He walked over to the door and rested his hand there momentarily.

Spock.

How long had he been foolishly in love with Spock? More pointedly, how long had it taken him to realize it? Too long.

Jim knew he felt a great deal of affection for Spock, knew that his feelings were deep and that he felt such a comfort knowing Spock considered him a friend. But when it occurred to Jim that Spock meant more to him than anyone, any woman he’d ever been with, anyone really, then he began to analyze things.

His own behavior could only be considered flirting, borderline outrageous, and the more he analyzed himself the more he realized he really had been at it for a long time. He was surprised Bones hadn’t called him on it for had the situation been reversed he certainly would have teased Bones.

And when he first recognized it, he had tried to curtail it. Spock didn’t seem to respond much, and Jim didn’t want to make Spock or anyone else around them uncomfortable.

Eventually, though, he hadn’t been able to stand it and he’d gone back to his usual flirtatious behavior. Not that it did any good.

With a sigh, Jim left the shared bathroom and returned to his quarters to get comfortable for the night. The holiday season prior, his mother had sent him a pair of pajama pants with holiday lights adorning them, so he put those on and then grabbed an old worn T-shirt he’d saved from his long ago Academy days.   

He obtained himself a glass of eggnog from the synthesizer, added a bit of brandy and headed to his desk.

“Computer, shuffle holiday music.”

He pulled up the bridge logs, computer recordings and all, figuring if he tortured himself with them long enough, he’d finally give it up and realized Spock simply didn’t harbor any secret feelings for him just because he did for Spock.

 The first few he observed were nothing special and pretty much what Jim had expected to find: nothing.

But then he played the bridge log from their mission to Eminiar IV.

Spock said, “A feeling is not much to go on.”

“Sometimes a feeling, Mister Spock, is all we humans have to go on.”

“Captain, you almost make me believe in luck.”

There was just the barest hint of…amusement, affection there.

Jim leaned in.

“Why, Mr. Spock, you almost make me believe in miracles.”

And then, there was that little raising of his eyebrows before Spock turned away and went back to his station.

Okay, well, there was something there, but…

Jim frowned, took a big sip of the eggnog, and pulled up another entry.

“I don’t understand why it gives you such pleasure to have me proven wrong.”

“An emotional earth weakness of mine.”

And then he pulled up another.

“Has it occurred to you that there’s a certain inefficiency in constantly questioning me on things you’ve already made your mind about?” A little smirk.

Jim leaned in so close now his nose almost touched the screen.  

“It gives me emotional security,” Jim replied, looking sly and flirty. Ridiculous really, even if he did say so himself.

Spock blushed and smiled.

Damn it! He blushed and smiled.

And…

Jim slammed his fist on his desk almost sending his eggnog flying.

“Spock!” he yelled before he could stop himself.

The door to their shared bathroom slid open and the man…Vulcan…appeared himself.

“Jim? Is there something wrong?”

“Wrong?” Jim laughed and leapt out of his chair and over to where Spock stood. “Wrong, Spock? No. There’s nothing wrong. Absolutely nothing!”

“Captain?”

Jim seized Spock’s forearms pulling him closer until they were face to face, nearly mouth to mouth.

“Spock. I…”

Up went the eyebrow.

“I have these…feelings.” He smiled a little. “Earth feelings.”

“I don’t understand.”

Jim nodded. “Probably not. Join me tonight? Chess? A glass of eggnog? On Earth, it’s traditional to spend a night like this with the one being that’s the most important to you.”

“I thought that was Valentine’s Day.”

He laughed. He was full of mirth. “That too. But see, that’s still months away, and I find myself wanting to spend this day with you, this night, with you. Only you. Do you maybe understand now, Mister Spock?”

He leaned up just a little, placing a very chaste, tentative kiss to Spock’s cold, stiff, unyielding lips. And if he’d miscalculated…

“I would like that,” Spock replied. “But if you will give me a moment, I would like to change, and then I will return.”

Jim swallowed and nodded. “Anything. You can have all the moments you need.”

But as it turned out, Spock was back remarkably quickly, and he’d taken off his uniform and put on this big brown, rather fuzzy robe, and Jim tried to remember seeing Spock in anything quite that casual before, and honestly he didn’t care, he was seeing him now, and it was all just a little crazy, but he thought that maybe this was the best holiday season he’d ever had.

“You look…amazing,” Jim said softly. “What can I get you to drink?”

Spock paused only a moment. And the little faint blush was back. “Hot chocolate?”

His eyes shining, Jim smiled. “Coming right up.”

He moved over to the synthesizer and Spock moved up close right behind him. There was a charge in the air or something, because Jim turned from the synthesizer as it made the chocolate and ended up in Spock’s arms. Pulled there or going there himself, it little mattered, because he was there, being held by Spock and he held Spock right back.

And Spock was the best present Jim had ever received.

Jim’s holiday pajama pants!