A/N: Heyyyy, neighbors! So, this is a quick little piece that's associated with the project I'm working on right now, though can be read standalone just fine. This went on further than I had expected, but I feel it's more complete this way. Um, there's suicide ideation in here, so if that is a road you feel better not walking down, then you may want to skip this fic.

As for that project I mentioned... I'm almost halfway through and actually plan to edit! Stay tuned, but maybe not so closely tuned. Enjoy!

This was more than cosmic irony, Leonard slowly realized as the sound of rushing blood faded from his ears. Such a concept was too small and weak to fully encompass the meaning of this event. No, it wasn't irony… it was poetic justice. That's exactly what this was.

It seemed to be a McCoy's destiny to die young, and never by accident. He, now confirmed, had xenopolycethemia, his mother, Earth's last cancer, his father…

McCoy twisted his pinky ring as his thoughts began to whirl. Poetic justice. He knew exactly why xenopolycethemia had developed now. It had just been waiting for the right moment to enact its due vengeance. This was his reckoning. This was his penance.

Jim would never understand.

That's why he asked Chapel not to tell anyone. He knew far too intimately what it was like to watch your loved ones wither and die.

Damn her.

Jim was mature. He was the captain of a starship; he had to be. McCoy figured that both of them were hiding behind the logistics of rank. It was his duty as the Enterprise's Chief Medical Officer to inform the captain that the Chief Medical Officer had a terminal illness. In kind, it was Kirk's duty as Captain to immediately file for a replacement Chief Medical Officer before the one-year deadline became critical. Starfleet was not tolerant of procrastination.

Neither of them could admit that he was dying.

Well, to each other, at least. McCoy could admit it to himself. He was a doctor, after all. Before Chapel decided to take matters into her own hands he'd had plenty of time to be honest with himself if nobody else.

Always blunt, he didn't sugarcoat the facts as he looked over the results. His red blood cell count would continue to rise to dangerous levels until his blood ran as thick as syrup. His spleen would swell and extremities bloat as the risk for thrombotic events skyrocketed. In the last few months he doubted he would be wholly mobile… certainly not if he was constantly undergoing phlebotomies. Then he would just drop dead from the final stroke… or heart attack; the two would be duking it out at the end.

A year at most to live… but an extraordinary decrease in quality after about six months.

McCoy wondered, often, if he would react anything like his father did. They had almost lost each other in denial until the grim, ugly truth finally stared both of them down. The difference was McCoy had already been on the other side. It was heartbreaking to watch your family suffer, and the Enterprise had become his family. He couldn't put them through that.

For a while, he had thought about going home. It would be wonderful to hug Joanna one more time, or to feel a humid summer breeze again. Oh, Joanna…

Maybe it was actually more than poetic justice. Maybe this was a curse. He barely had any memories of his grandad… maybe McCoy's were just destined to kill their fathers.

No. What he did to David McCoy nearly destroyed him… he would never put Joanna through that.

Or Jim, for that matter. That might even be worse. McCoy hoped he wouldn't go through with it, do that to himself, but if he was so delirious he didn't know what he was saying then Jim… Jim would still have to wrestle with that. Truth be told, Spock would probably be the only one who could go through with his wishes… but would that drive Jim and Spock apart? He couldn't do that to Spock. The man already had a bad habit of refusing to deal with his emotions.

It terrified McCoy. He knew what was coming, but it didn't feel real yet, so he didn't know how he would react. Would his constitution be that weak? Would he beg for death? Like father, like son?

Leonard's mama, rest her soul, always said he was a stubbornly independent boy. McCoy never let somebody do something he could do himself.

There was still some time. He would take care of the details: a final message to Joanna, Jim, and Spock; putting his estate in order; finalizing his will. Life would still go on for another few months. It would go on until just before the moment he deemed himself too weak to pull the trigger on a phaser.

Fortuitously enough, his dedication to normalcy led him to a way out. Natira was young and love-struck, but would still have plenty of options once he was gone. She seemed to take it in stride that they would not have long and McCoy realized he had a way to spare his friends the pain.

No one would have to deal with his corpse on the ship if he stayed behind on Yonada. Jim wouldn't have to find him in his cabin, Spock wouldn't have to go over his last will and testament looking for errors… they were all perfected by now. The discovery had been the one thing preying on his mind since he decided to handle his condition himself. Now, the agonizing cleanup was suddenly solved.

Jim still didn't understand. McCoy wondered if his friend actually thought he was staying because of a chance with Natira. Her company would be appreciated, yes, but she was prepared for his death since their introduction and Jim and Spock were not.

Spock, though… Spock seemed to look past the surface-thin romance. McCoy knew he rejected it out of hand, for such human things didn't make sense, but he was still probing, still searching for the reason.

"Your decision to stay is illogical."

McCoy almost wanted to berate him.

"Is it, Mr. Spock? Is it really?"

All of their studies in parallel universes had led McCoy towards a healthier appreciation of possibilities. Perhaps, in one universe, his plan worked. He was left in peace on Yonada and well-tended to until the day came to make his last decision. In another universe, the Enterprise never met Yonada. He and Jim would have a somber drink in the captain's quarters. The disease would really be showing on him by then, but his hands would never shake. Jim would be glum.

"I wish there was something more I could do."

He would reach over and pat Jim's knee. "You can't punch everything, Jim."

"But I could do something."

"No, you can't. Consider these my last words if you have to: don't blame yourself."

He would soak in every moment of that conversation. Whenever he ran into Spock, either before the drink with Jim or on the way back to his quarters, he would tell him, just once, how much he respected him. The Vulcan would be too surprised to follow him home.

His decision would be made in his quarters instead of on Yonada.

But no, in this universe, where the odds didn't give a damn, he just so happened to be saved.

A cure for his illness, out of thin air. It was as bold a second chance as Leonard had ever seen. It worked, and suddenly he didn't have half a year left, but half a century or more.

He didn't know what to do with himself.

His death was perfectly in order, but his life was not. The replacement CMO wasn't coming. His health was getting back on track. Duties in Sickbay and towards the crew called once again. What had just happened?

Denial plagued him for several weeks. At night his dreams whispered that the cure hadn't worked, that the xenopolycethemia was still there, and he would wake up confused because you don't wake up after shooting yourself.

The resulting existential crisis led to a more thorough evaluation on the meaning of life and its purpose. McCoy had long ago concluded that he was here to save lives, but it took some time to get back into the swing of things. Perhaps he was supposed to do something else in addition to being a doctor? Or perhaps he simply wasn't done saving lives yet?

He was so confused. How does one make peace with life after making peace with death?

Minara was… ill-timed, at best.

The choice was stinkingly obvious to McCoy. It was almost stupid how much the other two agonized over who should go. McCoy had made the decision months ago.

All that came of it (and damn those odds, 87% chance his foot!) were the same questions he asked himself vocalized by Jim and Spock. No, he didn't know why he did that (yes, he did). No, he doesn't understand what that would mean, no he doesn't know why he's here, no he doesn't know the point, damn it, he doesn't know!

"I never gave you permission to be a martyr," Jim told him sternly.

Exasperation struck hard as he struggled to figure everything out. McCoy was more snippy in Sickbay, agitated on the bridge, and flustered in the halls. When anyone asked what was wrong with him he didn't know how to answer. It was no particular thing, he was just fretting over the meaning of life!

Inevitably, such lofty concepts drifted down to land between him and Spock.

They followed the standard procedure: barb and retort. Spock argued for evolution, McCoy argued for greater meaning. In a rare moment of privacy, however, the formula dropped.

"Why are you here, Spock?" McCoy asked, far quieter than normal.

"I am here to serve out my duties as First Officer on the Enterprise," Spock answered promptly.

"No, I mean, what is your purpose here? You could do a lot of things, but you're here. Why here?"

Spock answered him a little more slowly. "If you are seeking to derive meaning for my presence based on my location…"

"Don't you ever wonder if you chose the right path? If you're living your fullest in the right environment?"

Spock contemplated him. "I cannot give an accurate answer concerning my position on the Enterprise in the 'grand scheme of things' because I do not have a full picture of this 'grand scheme' since the future is unknown. However," his tone changed slightly, and McCoy leaned forward like a flower finding sunlight. "I believe I can say that for right now I am best situated where I can fulfill my full potential. I do not know if this will remain true 10 years, 5 years, or even 1 year from now, but for right now I am 'where I'm supposed to be', as you would say."

It… made sense. It may not even be wholly logical, for which McCoy was proud of Spock. The words hit him with a force he hadn't felt in a while, and hadn't realized he missed. He blinked rapidly to get control of himself.

"Wise words, Mr. Spock," he said softly, giving him a watery smile. "Spock, I… I don't believe I ever properly thanked you for your role in the Fabrini cure."

"You did, Doctor. Though may I remind you it was only logical to pursue their medical databanks in an effort to save you, and unknown others, from xenopolycethemia."

McCoy saw right through him and half-laughed. "No, Mr. Spock, you saved me from more than that, more than you'll likely ever know. Thank you, Spock."

Spock tilted his head at him, lost at the direction of the conversation. "Your thanks are illogical."

"No, Spock," McCoy stopped him, exuding world-weariness tinged with an aged, delighted peace. "In this situation, thanks are extremely logical. Extremely."

Spock beheld him for a moment, then inclined his head. "Then you are welcome, Leonard."