A/N - Hey, so this is my new story Vulnerability, and it centers around Kirk and McCoy. I really like the idea of this pairing and after a few weeks of writing, reading, and watching Star Trek Bones is probably my favorite character. Not to mention the sarcasm and humor is a big bonus and the two actors that play McCoy definitely aren't bad either. Anyway, I hope you like the story and I can't wait to hear what you guys think of it.

Vulnerability was not something befitting of a Starship Captain. The crew could not see him in a moment of weakness, no matter what caused it. That was why James T. Kirk hid his pain away, even from his best friend. He could be beaten, bruised, stabbed, or shot and he would never let on about his condition until he was found out. His crew admired him for his strength and dedication; they knew he was putting them before himself. No one saw it as a weakness, no one questioned that he would take care of them and keep them safe.

Jim knew he had to keep that face in place in order to keep the respect that he had fought so hard to earn. And as said before, no matter what he was going through, physically or mentally, he would push it into the back of his mind to be dealt with privately. To him, being vulnerable was a weakness, and James T. Kirk was anything but weak.

He went through hell as a child and soon learned that when he cried or showed an ounce of pain that his tormentor was encouraged. Jim was small but smart. He took the abuse and showed nothing, just waited till it was over and he could hide in the barn loft until he was ready to face the world. As he got older he learned to hide it quicker, and soon it took no effort at all. His mask fell into place and no one could tell that something had happened to the young man.

Well almost no one. There was only one person that could truly read James Kirk, and that one person was his Doctor and his best friend, Leonard "Bones" McCoy. Only he could see the pain that was hidden deep in the clear blue eyes, only he could see when his friend was hurting. McCoy never pushed him to reveal the information because he knew that Jim would just close up, so he just patched him back together physically knowing that when Jim was ready, he would be there to fix him mentally.

After his divorce, Jim was the first good thing to happen to him. As weird as it seemed to him, McCoy was drawn to Jim; his confident manner, his smile, bright blue eyes, lean body. Everything about Jim fascinated him and he wanted to know more. He was in love with Jim Kirk.

He never told anyone, never showed any of this outwardly, especially to Jim. McCoy suffered silently and soon learned to be content with being Jim's friend and right hand man.

As usual, when things were quiet in the sickbay Chief Medical Officer McCoy would sit at his desk thinking about his best friend when there were no pressing matters to attend to. He leaned back in his chair and tried to work the pieces of the Jim Kirk puzzle together in his mind when he was brought out of his thoughts by an all too familiar beep.

"Spock to Doctor McCoy."

"McCoy here, what can I do for ya Spock?" McCoy laughed to himself as he pictured the emotionless half-Vulcan roll his eyes.

"The Captain left his shift a few minutes ago after receiving a private message from Star Fleet. Seeing as this is a very rare occurrence, I was wondering if you had seen the Captain."

McCoy frowned and leaned on his desk, "No I haven't. I'll take care of it Spock." He barely noticed that the transmission ended. Something was up, but he couldn't press Jim for the matter. He couldn't push the man that he cared for away; he was all Jim really had.

Once his shift was over he ate in the mess hall and made his way to his room, which was close to Jim's. McCoy was happy about this. It was easy to check up on Jim when he needed to, and he felt good knowing the man was so close to him. He showered and changed into some casual clothes when he heard another beep.

"McCoy here." He was startled at the voice that answered him.

"Bones? You busy?"

He shook his head forgetting that Jim couldn't see him. "No…why Jim, what's up?"

Even over the speaker he could feel the hesitation that was emanating from Jim. Something was beyond wrong if Jim was calling him and he could sense this kind of desperation in his voice.

"Can you come to my room? The door's open."

"I'll be right there Jim." he said and ended the transmission. He ran his fingers through his damp hair and made sure he looked presentable before walking down the hall way.

Just as Jim said the door was open and he walked in to see Jim sitting at the small table, a drink in his hand and his gold Captain's shirt tossed to the side. "Bones." he said smiling gently and put a drink on the table for him.

McCoy sat down and watched Jim. He sipped the drink and smirked, "Strong stuff Jim."

A shadow of the familiar smirk was sent his way. "Sometimes situations call for it." Jim lapsed into silence again and McCoy waited for Jim to speak. Hell, if sitting there helped Jim then he would sit there for hours.

"She's dead."

McCoy looked at Jim, "Who's dead?"

Jim looked at his drink, swirling it around in the cup before downing the rest of it in one large gulp. "My mom."

Silently, McCoy took in Jim's features as he spoke. "She hung herself." Jim's voice was weak, but his grip on the glass was getting tighter. "I mean of all the ways to do it she picked that? And she did this to herself because of him."

McCoy knew who he was talking about Frank, his step father. The man had treated Jim horribly as a child and that was about all he knew. He had made guesses that Frank was the reason Jim was scared of water and so withdrawn when it came to certain things.

"She loved him more than me, more than Sam. She didn't believe me when I told her that he hit me, held me under water till I almost passed out. She was so blinded because she thought she found someone to replace Dad.

"I thought she would be better off when the bastard died. She called to tell me and I had to try so hard not to smile. She…she told me she didn't know if she could survive Frank dying, not after losing my Dad. Frank died two months ago. I guess she was even more blind than I thought she was."

McCoy watch Jim and realized he had never seen Jim so open, so vulnerable. He knew it was taking everything Jim had to talk, but it had become too much and he could see the tears welling in his eyes. Wordlessly, he reached out and took Jim's hand in his. He gave a warm and comforting smile to his friend and Captain. He was internally relieved when he saw relief on Jim's face. Jim trusted him enough to see him like this, this was another thing Jim didn't have to worry about in front of McCoy.

"Come on Jim, let's get you ready for bed and I'll stay with you for a while ok?"

At first Jim was hesitant, McCoy could see that but soon a look of thanks and need was on his face, "Thanks Bones." Jim changed while McCoy picked the place up a bit. He sat on the bed as Jim walked over. The Captain bit his lip.

"It's alright Jim, I'll keep quiet."

"I know Bones." he said and slipped under the covers.

McCoy watched him, fighting the urge to run his fingers through Jim's hair. He let his arm wrap around Jim's shoulders when the younger man rested his head against his chest. He soon felt Jim's body shaking with silent sobs and he held him tighter.

"I gotcha Jim." he whispered, keeping their bodies close.

"You're all I have left Bones." he finally said. He looked up and McCoy felt his heart break at the look of trust and vulnerability in the blue eyes.

He leaned down and kissed his forehead, "And I will always be there."

Jim swallowed and shifted so he was at the same level as McCoy, "Promise?"

McCoy nodded, "Promise."

Jim smiled softly and leaned up pressing his lips to McCoy's. he closed his eyes and moved closer to his friend.

McCoy froze, knowing it was wrong, he shouldn't, he couldn't take advantage of Jim like this. But it felt so good. His will broke and he felt himself returning the kiss and pulling the slightly smaller Jim Kirk to him. The kiss remained gentle and McCoy could taste the tears that had been falling.

When they pulled apart he found himself staring into trusting and pleading eyes. "Still promise?" Jim asked, his voice just a whisper.

Smiling warmly McCoy nodded, "Still promise."

He laid down and held Jim who kissed him again before resting his head on McCoy's chest. McCoy played with his hair thinking to himself, Let's see how you feel about this in the morning Jim.

A/N - So there is the first chapter. Let me know if you think I should leave it at this or continue with it. I hope you guys enjoyed reading it as much as I enjoyed writing it. Also, if you haven't checked it out and like Kirk/Spock check out my other story, Come Back to Me Spock. Thanks, as always.