.o0o.

That had to have been the longest day of his life, McCoy decided as he sprawled back in his own bed. Spock was in his own quarters meditating, which was just fine by him. He could do with his own meditation. Or maybe some brandy. But even though he'd deemed it acceptable if they were both off duty for an extended period of time, Spock didn't like the feeling of being drunk, so McCoy didn't get out the alcohol.

Instead, he crossed his fingers and stuck his arms behind his head, looking up at his bland ceiling. He wanted to talk to the captain about what had happened on that planet, but he wasn't sure how to address the situation. Jim had powered through the day despite losing his brother, his sister-in-law, and nearly losing his nephew. Despite the impending loss of Spock as his First Officer. Despite nearly having to cause the death of a whole planet of colonists. Those weren't just things a person could brush off, even a captain determined to complete his mission.

And McCoy knew how keenly Jim had felt those events. He hadn't just seen Jim's expression and extrapolated from years of knowing him, nor had he just felt an echo of grief from his own pain at the situation. McCoy had felt Jim's pain in the same way he'd grown accustomed to feeling Spock's emotions. And wasn't that a doozy? He shouldn't be feeling other people's emotions. Yet whenever he'd reached out to offer comfort in the form of a touch, he'd nearly been bowled over by the strength of Jim's grief. He'd been shocked and amazed that a man could feel so strongly and continue on as if nothing at all was happening in his heart. Then again, this was Captain James T. Kirk and he wasn't known to do anything halfway.

'Dr. McCoy.'

McCoy frowned. 'Shut up, Serin.' He could practically hear the eyebrow being raised. Were Vulcan children taught that in schools? He could just picture the teacher coming to the front of the room and saying: and now, children, the eyebrow. This will be the only acceptable form of displaying emotions.

'Eyebrow manipulation is not a part of Vulcan curriculum.'

McCoy convinced himself it was more annoying than humorous. 'I'm kind of busy here.'

'You are not.' Definitely annoying. 'This is the first time you have responded to us.'

'And you took 'shut up' as an engraved invitation to continue this conversation?' McCoy snapped.

'We apologize for going against your wishes, but-'

'As if having one Vulcan in my head weren't bad enough, now I have two. At least Spock goes away when I tell him to. Not to mention asks permission before manipulating my brain.' McCoy grumbled. 'Look, I appreciate what you did for me with the Romulans and again with giving Spock back his soul and all, but that wasn't a standing invitation to my mind.'

Serin paused briefly. 'Unfortunately, there was no opportunity to discuss our continued access to your mind with you before this point. We were unaware of it until some time after you had already departed from Andar IX as we were still quite fatigued from prolonged displacement. As for the manipulation, we do not know what you mean.'

'So you're saying you had nothing to do with those dreams.'

'We did not.' Serin protested. 'We suspect it may be a reaction to the link between our minds.'

'I don't want to be linked to anyone else's mind!' McCoy growled. He still wasn't entirely sure he liked being linked to Spock's mind, though he was slowly coming to the conclusion that he did. 'Don't tell me this is some other Vulcan marriage link.' Why do things like this keep happening to him?

'It is not.'

'Well, good.' The doctor fumbled. 'Then you won't have any problems leaving me alone.'

Serin took a while to respond, so McCoy took that as compliance and decided to head to Kirk's quarters. Serin had yet to bother him while he was talking with someone else, so he thought he might as well get started right away. It was very late according to ship's time, so late it was early again, but he knew Jim well enough to know that he wouldn't be sleeping tonight.

'We understand your reticence in talking with us; however, we cannot change the fact that our minds are linked.'

McCoy refused to acknowledge him, beeping for entrance at the Captain's chambers.

'Ignoring us will not erase our connection.'

He pressed the button again.

Jim appeared at the doorway a minute later, completely unsurprised to see him standing there. He could feel the dark emotions covering his friend like a shroud. "Hey, Bones. Spock kick you out?"

McCoy ignored the jab. "We should talk."

"I was actually sleeping." Jim replied, then quickly corrected himself, "Getting ready to sleep."

"Uh-huh." McCoy raised an eyebrow. He didn't believe it for a second, even if he was wearing his sleeping clothes. "Can we talk?"

Sighing, Jim moved out of the way and let the doctor come in. "Something to drink?"

McCoy shook his head and that sat down awkwardly across from each other. "I'm concerned about you."

"Bones, I'm fine."

"Dammit, Jim!" The sound burst from his throat and for a second, McCoy was surprised it had slipped out almost without his notice. His head was swimming and he thought it might not just be his own emotions cluttering his thinking. He cleared his throat and tried to soften his tone. "You lost your family down there. I don't care how tough you are, Jim Kirk, but you are not heartless."

Grief was bubbling up inside of the captain but he didn't seem willing to acknowledge it. His face was tight, his eyes grim. His voice was rough as he spoke the clipped words. "We were hardly family. We barely spoke. Peter didn't even consider staying with me as an option."

McCoy nodded, inching closer to his friend. "He probably didn't think a starship captain could take on a kid."

"I didn't even offer. I think I was just afraid of hearing him say no."

"Jim..."

"I was a terrible brother. Sam died thinking I still blamed him for Tarsus." McCoy didn't ask about Tarsus or why his brother had been involved. He knew Jim had been in the surviving half of the massacre and that was enough for him to draw his own conclusions. "I didn't protect them."

McCoy inched closer again, wanting to reach out a hand but slightly afraid of what he'd feel from it. "Jim, there was nothing you could have done differently, no way to know that this was happening."

"If I had kept in contact... maybe there were signs that they'd seen and we'd missed." Jim shook his head. "If we'd pressed just a little faster, we might have even saved Aurelan."

"Aurelan was already taken over and for her, that would have been a death sentence either way. You saved their son, and you've got to know that Sam would be happy about that."

Jim didn't even seem to be listening to him anymore, but McCoy found it more reassuring than anything else. He thought it was about time that the captain have his own breakdown and faced his emotions. "Oh god, I'm never going to see him again." His eyes were red rimmed, but if he was crying, McCoy sure as hell wasn't going to bring it up.

Then, Jim crossed the distance and pulled him into a hug, clinging to his chest, almost as if he were desperate for his touch. McCoy wrapped his arms around him as a tidal wave of emotion crashed into him: grief, pain, regret, loss... The doctor was glad that he was already sitting or he was pretty sure they'd both be on the floor by now. He clenched his teeth and held on tighter.

As the waves slowly began to die down, and he came aware of himself, he found that Jim had fallen asleep half way falling out of his chair and that Spock had joined them in the room, perhaps going through the adjoined bathroom, which needed no permission to enter. Spock helped him carry their friend the few feet it took to get him into bed.

"I felt your distress." Spock said by way of explanation as McCoy tucked the captain in. Jim looked so young and peaceful lying there. It felt wrong somehow that they should pile so much on his shoulders.

McCoy found that he hurt. He found that he ached in a way that had nothing to do with his body. He just wanted to curl up in a cave and die.

Spock's eyes rested on him warily.

He pushed against the Vulcan and stole a demanding kiss. It was like a fire keeping the clouds of grief at bay, warm and brilliant. McCoy kissed him again, harder than before, like he could erase all the negative emotions.

Spock pulled back. "Might I suggest my quarters tonight?"

McCoy had the briefest thoughts of Serin, wondering what exactly the link would convey to him, but quickly decided he didn't care. He nodded enthusiastically, letting Spock lead him back to his room. It was warmer than he liked it, but he couldn't be bothered to fix the temperature. Couldn't be bothered by anything other than getting his lips on Spock's again. He could feel Spock's own enthusiasm and affection for him, which egged him on, but was slightly concerned by the wariness that hadn't left him.

He pulled off his own shirt, dropping it where he stood and then worked on getting Spock's off. As soon as it'd been removed, he was back for more hungry kisses. McCoy ran his fingertips over the Vulcan's chest in a way that he knew the other liked and felt an answering pleasure. McCoy worked his way downwards, kissing and stroking Spock's smooth muscles until he was kneeling with Spock's buckle in front of him. Eyes met eyes and McCoy undid the bindings on the pants before pulling them down, taking Spock's boxers with them.

McCoy paused to look at Spock in a way that had nothing to do with medical interest. "Sit." He demanded breathily.

Spock sat.

Swallowing, McCoy found himself leaning in eagerly to take Spock into his mouth. He'd never given a blowjob before, had never wanted to before, but he'd had enough of them to have an idea of what felt good and try to imitate that. This was the farthest they'd gone so far. Most of their physical affections manifested in touching one another, McCoy finding himself mirroring Spock's special interest in hands and finding Spock's hands in particular both skilled and sensitive.

McCoy found himself enjoying the act and wondered at his previous aversion to homosexual encounters. Would he enjoy them now if it were someone other than Spock, he wondered. He could feel a trickle of amusement from Spock. He must have been projecting. McCoy found that he even liked the taste that seemed so very Spock.

Spock's hands wound into his hair, but he didn't try to control his movements, which McCoy was decidedly appreciative of. He was very sure that his gag reflex would not disappear even in the light of a surprisingly pleasurable blowjob.

"Stop." Spock was suddenly requesting, releasing his hold on his hair. It jarred him back to reality.

McCoy pulled all the way back, taking a few deep breaths. It hadn't been that bad, had it?

Spock graced him with the tiniest lift of the lips. "It was not at all bad, Leonard."

'Then why'd you stop me?' McCoy generally preferred to use his mouth to talk, but somehow it was easier to discuss intimate details silently.

'Something is not right, Leonard.' Spock responded, worry slipping across the link. 'While I feel the physical pleasure in your touch, that is the only sensation I'm experiencing.' There was the pause that nearly always proceeded Spock admitting anything to do with his emotions. 'I find that I am not feeling the emotional pleasure that has accompanied it in the past.'

McCoy tossed the words over in his head as Spock stood and pulled up his pants. Physical pleasure without the emotional pleasure. Was that the same as forcing physical pleasure from someone? Was he to blame in some way? He'd found the experience especially pleasurable this time. How had he missed that Spock wasn't there with him?

"I have a suspicion as to the cause. I would like for you to accompany me to Sickbay to run a few tests."

"What kind of tests do you think would help?" McCoy looked up at him but he wasn't feeling antagonistic at all.

"I'm uncertain at this point."

McCoy pulled on his shirt. "At least we don't have to worry about confusing our shirts anymore." He commented because silence was awkward, but doubly so when you were just stopped mid blowjob.

"On the contrary, Doctor," Spock returned, "We are more likely to confuse our shirts now that your promotion has been officially recognized." McCoy smoothed down his shirt self-consciously before leading the way out towards Sickbay. "Indeed, without your general wear on your uniform, our shirts have become indistinguishable."

"General wear? I suppose your shirts have no sign of usage." McCoy groused. People tended to assume he started these arguments, but Spock was frequently more guilty of baiting him intentionally.

"Your shirts do not reflect a care in maintenance."

"They look exactly the same!" McCoy realized that Spock was attempting to distract him and grudgingly let his appreciation show. He waved off the night shift nurse and hopped up onto a biobed.

"Please lay back." Spock requested.

"I'm the doctor here." McCoy responded with good-nature, leaning back against the pillow as Spock observed his readings. He crossed his legs impatiently as the Vulcan then retrieved a medical tricorder and ran it over him as well. "Will I live?"

Spock raised an eyebrow. "Undoubtedly. However, I am no closer to determining if my hypothesis is correct."

"And what is your hypothesis?"

"A blood sample, Doctor."

McCoy complied, taking his own sample and following Spock into a lab at the back of Sickbay. Together, they examined the blood through a series of tests that Spock suggested. Each one seemed as useless as the last. About an hour later, McCoy let Spock run his own tests and looked through the analysis given by the computer. On his second read through, he found himself baffled. "What the hell?"

"Doctor?"

"Sorry, let me just try this again." So McCoy took a second sample of blood from his arm and ran it through the machine again. It did not take long as McCoy knew exactly what he was looking for. He set down the PADD.

"What have you discovered?"

"My DNA has been... altered somehow."

"Ah."

"You don't sound surprised." He knew for a fact that the Vulcan didn't feel surprised either. It kind of irked him. Of course, if Spock had known that this was likely, he would have checked that possibility first. Which meant that Spock had simply surmised a conclusion that fit with the given evidence.

"I believe you are absorbing other people's emotions as a result of your previous integration with the Indyrin. I had thought that perhaps a portion of the Indyrin had remained behind when you were separated, but this does not seem to be the case. Instead, you seem to have been changed."

"Goddammit." McCoy didn't like the sound of that. "That explains Serin's insistence that we were linked."

Spock raised an eyebrow. "Perhaps it is time we talk with Serin."

"We?" Spock raised his hand in a sign that he wanted to meld. McCoy figured he was already in his head anyway and allowed the contact.

'Serin?' McCoy called out.

The response was distressingly immediate, like Serin had been lying in wait. 'Doctor McCoy. Spock.'

'What has transpired to change Leonard's DNA?' Spock questioned without pausing for pleasantries.

'As we were trying to explain to the doctor earlier,' Serin began and who said Vulcans were above gloating? 'When he sparked the Indyrin growth, it was designed to bind the two together. Dr. McCoy was meant to change until he began something between an Indyrin and a human so that he could live inside of the Indyrin. He was meant to become what I have become. The Indyrin did not know that they would be separated, and it was not prepared to be separated and thus started the process immediately. It made him more like itself.'

'I'm right here.' McCoy interjected. 'You don't need to talk about me like I'm not. How much was changed?'

'It is difficult to be certain. Hopefully, what you have experienced so far will be the extent of it. You will be able to feel others' emotions, and you may even need to take some of them. It is difficult to tell if it is necessary for your survival yet, but you clearly have the ability to absorb the emotions.'

McCoy tried to ignore the implication that Serin was very aware of what had transpired over the last few hours. But it did make sense. It explained why Kirk had fallen asleep; McCoy had actually removed his grief from him and allowed him to relax. And from the other washes of emotion, he'd likely done it before. He'd apparently done it to Spock, too. 'And I'm also linked to you.'

'You are a part of us now. We cannot help but want you to return.'

Spock didn't like the comment any more than he did. He changed the topic. 'Will the doctor continue to change?'

'No.' Serin assured them. 'Any changes were made immediately and stopped as soon as McCoy was released from the Indyrin.'

'How come it took so long for these... effects to start then?'

'You are an empathic individual by nature. It is likely that these effects have been present for some time without you noticing. I believe your strong desire to assist your captain allowed you to subconsciously take on more than you had before.'

'But I've only heard you recently.' McCoy puzzled.

Serin agreed easily. 'Indeed. That was due to our weakness and not a lack of ability.'

Spock spoke up. 'Is there a way to undo what was done to him?'

'Gene manipulation is a field even modern medical science dare not contend with.'

'The Indyrin couldn't undo it?' McCoy asked.

'We do not have that capability.' McCoy figured he must be radiating as much displeasure as Spock because Serin continued, 'We believe you will come to appreciate this. You are well suited to sensing others' emotions. You may find it very useful. And the Indyrin are wise and powerful. As we have grown together, we've discovered many things of interest. For example, we have become aware of a nearby planet of intelligent life-forms who have just created their first warp drive. Federation scans of the area have yet to pick up any life-forms at all.'

It was an intriguing peace offering and McCoy decided to take it, for now. But he had one more question. 'Are you always going to be in my mind watching what I do?'

'You do not seem to understand telepaths or our link, Doctor. We will always be in our mind watching what we do. It cannot be helped.'

McCoy didn't find that comforting at all.

.o0o.

A/N: Serin keeps sounding sinister. It's supposed to be more like a que sera sera attitude, but the que in this case is kinda disturbing.

Thanks for the reviews! I figure you'll forgive me for not responding to them individually as long as it means I can post faster. It does. Also, the more reviews I get, the more motivated I am to post. So... you know.

God these chapters are long.