Gaila was, for once, stretched out on the bed studying. She was still half naked because, given the chance, she would spend every minute of every day in her underwear. Having grown up sharing a house with four sisters, it wasn't something that bothered Uhura.

"You're here – and alone!" Uhura exclaimed, dumping her bag on the floor and flopping onto her own mattress. "And ... studying? Gaila, is everything alright?"

"You buried your mother three days ago, and you ask me if I'm alright?" The smile that greeted her was tense and false. Spending so much time with Spock had taught Uhura to study people's faces as closely as their words and intonation. She didn't respond, just stared at Gaila and waited for her to spit it out. Eventually, she cracked. "Jim had sex with that blonde girl in your Advanced Klingon class."

Uhura blinked. "Oh. That bothers you? I thought you guys didn't believe in monogamy?"

"We don't. But we kind of ended up there anyway. I mean, we keep up with each other pretty well and neither of us were getting bored enough to look else where. At least, I didn't think we were."

"So this is 'hurt pride' sulking not 'broken heart' misery, right?" Uhura asked with a small smile.

"Pretty much. And I'm horny as hell with no one to turn to – not that I'll get any sympathy from you on that front." Gaila smirked and rolled onto her side, fluttering fiery red eyelashes at her friend. "Come out with me tonight? Men trust me more if you're there."

"No, men think there's a chance of a threesome if I'm there. Besides, I have plans," she announced with a small, secret smile.

Uhura could smile her secret smiles all she wanted, but Gaila could tell with one deep inhale of her rising pheromone levels what her best friend was intending. She gasped, eyes rounding in delight and surprise. "You're going to jump Commander Spock? Wow, weird timing."

For a tenth of a second, Uhura considered denying everything. Or at least refusing to comment. But she's going to want someone with whom to obsess over the whole experience, and Gaila will only smell it on her later and put two and two together. Besides which, it was strangely nice to have a conquest (or pre-conquest) to gloat about after two years of Gaila's stream of lovers. "Well, yes and no. He sent me the sweetest most awkward message while I was at home, and I just really don't want for him to feel like he has to handle me with kid gloves. It's been horrible, but I'm a big girl and I need support and distraction more than pity. And, unlike you, I consider sex to be an act of love. It's a sensible step, it's ... logical." She grinned, allowing a warm glow to partially cover the empty ache that she spent her days trying to ignore. "And his mother said something that made me think he might be receptive."

"You keep talking about his mother. Frankly, I think it's weird."

Uhura laughed half-heartedly throwing a pillow across at the other bed. "His mother's nice, and she understands her son well enough to give me tidbits of inside information."

Like any other boy in love, she thought. The words had imprinted themselves firmly on her mind ever since she first read them.

"Do you have a plan?" Gaila asked, sitting upright and looking as serious as Uhura had ever seen her look.

"A plan?"

The Orion sighed in frustration. "Commander Spock's a complex man. You need a plan. You can't just knock on his door and say, 'please sign for a booty call'."

Uhura rolled her eyes. "Because that was exactly my original idea." She shook her head. "I've thought about it a little. And I think the best thing is to be direct. He's not going to understand seduction – he's asked me about human mating rituals before, so I don't think it's been part of his study plan. Vulcans respect a direct approach."

"So you are going to jump him?"

"No," Uhura said, drawing out the vowel. "I'm just going to ... engage his human responses before his Vulcan side can start over-analysing the situation."

Gaila nodded firmly, lying back down on the bed. "Very logical. He'd be proud."

When the door chimed, Spock frowned and checked the digital time display. His internal body clock knew that it was twenty-hundred hours, but he appreciated the confirmation. He knew of no appointments, nor of anyone that would call on him at such an hour. Students and Commanders alike were, for the most part, out in the bars of San Francisco celebrating a last night of freedom. "Identify," Spock requested, frowning at his data PADD. It was a most inconvenient moment. There were lessons to plan and mid-terms to design, not to mention the latest programming bugs that had hit the Kobayashi Maru. Kirk would be taking the test in the morning, and Spock was determined the conditions would be more impossible than ever. If any cadet needed a short, sharp lesson in losing battles, it was Cadet Kirk.

"It's me. It's Uhura," said the familiar voice, digitised and resounding through his rooms.

Spock blinked and put aside his data PADD. "Enter," he said.

When she walked through the door, he stood to greet her. She lingered in the doorway, as though experiencing a moment of indecision. It did not last long, however, and she quickly crossed the room to join him. "Good evening, Nyota. I had not expected you to return to the Academy so-"

He was cut off by the forcible pressure of her mouth against his. The sensation, which had become familiar over the preceding months, was neither unpleasant nor unwelcome, and Spock was quick to respond. His hand came up to her jaw, fingertips resting lightly against her cool skin as he moved his lips against hers. Her movements were insistent, more so than during previous kisses. Breath puffed over his skin, the fingers of one hand digging into his shoulder as she pulled him close and held him steady. Nyota's other hand came met with his, fingers running over his knuckles. She covered his hand with hers, rubbing her fingers between his.

On the outside, Spock murmured against her lips. Not a word, just a sound, an involuntary unintelligible vocal demonstration which was, even under the circumstances, unacceptable.

On the inside, Spock's senses were steadily becoming overwhelmed. Heart thudding and pulse rushing, deep purple mist pressing against his glass box which suddenly seemed quite fragile. Spock attempted to pull away, and when he opened his eyes he saw that Nyota watched him closely. Her own eyes were dark, and she too was breathing rapidly. Her emotions flooded over his mind, making it difficult for him to separate his thoughts from hers. "Nyota, wait," he murmured, intonation rising at the end of the syllable. Nyota had clearly misunderstood the tone of his voice, confusing it with passion or need rather than the thinly veiled fear that swam through his desire.

She pushed hard at his shoulders. Spock could easily have fought her off, but her thumb was still grazing over his palm in a way that made his breath catch in his throat. His eyes fluttered shut as he felt for the stool beneath him, and Nyota climbed eagerly onto his lap. She was too close, much too close, and he could feel nothing but her – the pressure of her legs against his and around his waist, her mouth sliding across his cheek towards his ears, her hands on his. It should all have been pleasurable, and it was, but Spock felt himself reeling with the sudden sensory overload. "I don't understand," he said, reverting naturally to his own language.

Nyota's hand shifted to his wrist and, as her fingers brushed his pulse point, he heard her mind resound with the words Carpe Diem. A language, almost certainly, but not one with which Spock was familiar in even his most logical state of mind. She brought his hand towards her, shifted it so the palm pressed flat against her, and she curled his fingers around the soft flesh of her breast. The texture and weight and very slight bump that he supposed, distantly, must be her nipple sparked against his nerve endings. Spock's other hand moved to her hip. He intended to try and shift her away, to remove her from him so he could discern some reason to what was happening.

"Spock, I want you," she whispered against his ear, before taking the lobe between sharp teeth. It certainly did not hurt, in fact made Spock shudder, his hands clenching around her thigh and breast. And inside his mind, that deep dangerous purple, pressing and pressing against the glass.

"Nyota," he tried once more.

Without his notice, her hand had snaked between them. In his current position – legs slightly spread in an effort to balance her weight on top of him, leaning back marginally to place as much distance between them as possible – he had inadvertently allowed her the perfect access.

When her fingers skated over and then squeezed his erection through the confines of his slacks, Spock closed his eyes and watched the glass box shatter. Feeling enveloped him, rushing into every part of his mental being, entirely uncontrolled. Undulating purple and black and swirling blue brightened and crystalised momentarily into blinding white.

His hand gripped her wrist. He felt the contact distantly, as though in a memory. His eyes were open and he saw expressions of surprise and lust clouding Nyota's face. "No," he said firmly. Were he in his normal state of mind, he might have noted that his voice was significantly deeper than normal, a steely stern thread driving the single syllable home.

"But," she began.

He would not let her bypass him again, not until he had regained control. "You have to leave." Again, his tonality brooked no argument.

Nyota looked wounded – there was no other word for the expression. And Spock felt so much pain at the twisting greens of guilt that suffused his system, effectively over-writing the all-consuming lust she had brought about. But, as over-wrought as it was, his Vulcan side knew that there was no logic in attempting any sort of reconciliation until he was once more in his proper state of mind. "Please," he added, as a compromise, though the word was barely whispered.

Spock saw her swallow, and she stumbled awkwardly as she rose up off him. She might have been crying, but Spock could not tell because he had already begun to place himself in the meditative trance that, he hoped, would restore him to himself.

That night it took five hours for Spock to reassemble his emotional cube. It was an exercise in patience, if nothing else. Each metaphorical shard had been scattered to a distant corner of his mental landscape, calling him to pull together each and every thread of himself in the reconstruction. Some of the shards were very small, and others might have thought it unnecessary to search for them. But Spock understood, particularly after that evening's events, how incredibly important it was that he make this cube as resilient as the last had been.

He did not resent what his father would have called a failing. For, once it was allowed to control him again, the calm of his logic told him that the duress and circumstances had been severely against him. As a half-human, he could not expect the full emotional control that a Vulcan might exert under such pressure. It was foolish and illogical to think as much.

He did not resent Nyota, either. She was entirely human and could have no conception either of the complexities of Spock's emotions and the vicarious control he had over them, nor of the emotional implications of her actions. Even if she saw the brilliant electric blue and deep purple when they held a telepathic connection, she had no key to tell her what they meant.

Finally opening his eyes, Spock saw the room around him exactly as it had been. Everything was once more in its place, his own mind frame included. One aspect of damage control completed, Spock stood to handle the other.

It was one thirty in the morning, but Spock saw no logic in leaving the situation to brew until the coming day. Judging from what he knew of human behaviour, he very much doubted Nyota was asleep anyway. He requested a communications channel with her room, and waited for her to respond.

After two minutes, and a second attempt, her image appeared dimly on his screen. "Spock, it's half past one and I don't want to talk to you right now."

"You are acting emotionally to an entirely involuntary response, Nyota. I advise that you let me talk to you before your subconscious is given the opportunity to invent a situation that does not exist."

He saw her shake her head. It bowed and he was no longer able to read her expression. Pastel-hued hope swirled in his reformed emotional cube, but Spock ignored it. Nyota had not broken their communication yet, raising his chances of success by nine-point-three per cent. "I have no desire to be overheard by your room mate. Would you return to my quarters?"

"She's not here," Nyota said, her voice muffled. She looked up and, on closer inspection, Spock surmised that she had been crying. "And I'm not going anywhere. You can say whatever you have to say over the comm."

"You are angry with me. And hurt."

"Very astute, Spock." She took a deep breath, and Spock allowed her to speak. "I've always believed sex really doesn't matter that much, because intelligence and humour and love are so much more important. But that really hurt, Spock. You dumped me out of your quarters without any kind of explanation."

"I was incapable of giving an explanation, and offer one now."

"And my mother's just died!" she continued, seemingly without having heard him. "I don't get why I'm even explaining myself to you. It's not like you can expect me to be Vulcan. You wanted me – I could feel it, in your mind, like I do sometimes. You wanted me too, and you still rejected me. I just don't get it."

He lowered his calculations by six per cent, having incorrectly assumed her advances were an indication of having passed on from her grieving process.

"Go on then," she whispered, her voice slightly hoarse. "Let's hear it."

"I agree with your criteria for a suitable mate. We are of a similar intellect and disposition, despite the mitigating factors of our differing descent. And I find your company agreeable to an extent I have not experienced with any other person of my own age. Further to which, I have recently noticed I respond physically to you. As you so astutely put it, I have wanted you." She was leaning on her hand, the fingers covering her mouth making it more difficult to read her expression. Valiantly, Spock continued. "It is a reaction I have never experienced before. When you presented my body with such forceful stimuli, the matching emotional responses were ... overwhelming." He had considered trying to explain the metaphor of the glass cube, but doubted it would translate accurately. "Unlike true Vulcans, my self-control is incomplete. It is always present, but does not entirely hide my emotions from me. They are still there, but restrained. Because this has been the case since my earliest memories, I am unaccustomed to functioning without that control in place."

He thought he saw, for the briefest moment, a flicker of humour in her eyes. His chances of success rose by twenty per cent. "Are you saying I broke you?"

"Your analogy is flawed," he lied – for that was precisely what she had done. "But it will serve for the time being."

She sighed again, scrubbing a hand over her face. "You're here, which means Vulcans have sex without going off the deep end. Do you just need ... time, or something? To speak to your Dad, maybe?"

"Impossible," Spock said, trying very hard not to imagine that conversation. "And unnecessary. I am already aware that Vulcan reproductive systems are programmed to function every seven years. That is how we mate."

This sigh was frustration. "You're capable of sexual intercourse, Spock. Not to be crude, but you were hard."

With a firm mental hand, Spock clamped down on his natural response, which was to blush. There was no logical reason for it – it was a perfectly natural statement of fact, and certainly not something of which he should be ashamed. "Physically capable, I agree. But not emotionally. Not yet."

Nyota nodded slowly. She sat up straight and Spock suspected he may have succeeded. "OK."

"I have offered an explanation," he said softly, "But not an apology. Though I was unable to express myself in any other way, I am still sorry to have been the cause of your current emotional state."

"It's OK, I'm fine." She was lying, but it was the sort of lie Spock had learned not to question. "Are you OK now?"

"I have completed a lengthy meditation session and have every reason to believe my emotional control is functioning admirably." Nyota nodded slowly, and took a deep breath that turned into a yawn. Spock knew he should allow her to return to bed and sleep before the coming day. But first, his lips quirking slightly, there was a question he wanted to ask, and thought she might just be in a state to answer. "A query before you return to bed?"

"Sure, why not?" Nyota mumbled around a yawn.

"One of your criteria for selecting a mate was love. May I ask if I fulfil this aspect?"

She raised an eyebrow at him, shaking her head as she smiled. "I haven't forgiven you enough to answer that question yet." She let him wait seven seconds before continuing, "Ask me again in the morning."

A single stiff nod was all Spock's response. The pastel green hope within him redoubled its efforts, but Spock held it firmly in check. "Good night, then, Nyota."

"Night-night."

She cut the transmission feed, and Spock was left to anticipate her answer to the question he would be sure to repeat in the morning.