Disclaimer: Stargate Universe doesn't belong to me.
A/N: Takes place after Deliverance. Obviously non-canon after that. This was also supposed to be a quick PWP. Things didn't exactly work out that way.

"So, the e^x derived always remains the e^x, correct?"

"Yeah. It's one of the constants. It never changes."

Chloe looked at the screen a moment longer, memorizing the constant and then pointed at another equation.

"So, if I have a function f(x), which is multiplied by the e and I derive them both, I'm really only deriving the f(x)."

"Ah, not exactly," Eli said. "You are deriving the whole multiplication and there are different rules for that. Here, you've got x^n which derives to-" he waited for her to finish.

"- to nx^n-1, I know."

"Right. But x^n is only one part here, a function f(x), while the e is the function g(x) - forget about the fact there's no x for now - and so you have to derive it as [f(x)g(x)]' which is supposed to go like-"

"But the e is not a function in this case, it is a constant and Chloe was right in that she only needs to derive the function f(x), in this case x^n."

Both Chloe and Eli jumped in surprise, Eli looking more guilty than Chloe by far. Chloe knew he was supposed to be watching over the slowly being repaired shield system but since they had the laptop next to the console which was set up with a link from the bridge to feed over all of the relevant data, she didn't see any harm in it. Dr. Nicholas Rush, on the other hand, might. He walked over to where they were huddled over Eli's laptop and looked at the screen, sneering a bit.

"May I ask why the two of you would waste time with basics like that?" he asked Eli pointedly.

"It was my fault, Dr. Rush. I asked him to explain some things to me," Chloe wouldn't let Eli take blame for this. Rush looked at her.

"You should still be able to do this kind of mathematics in your sleep."

"And I can but I don't know why," she pointed out. "I know what the right answer is supposed to be but I don't know why it is the right answer. And I want to know."

"So you asked Eli to teach you?" Rush asked sarcastically.

"Hello, Mathboy?" Eli grumbled.

"Not the point, Eli," Rush told him as he activated his console. The control interface room was still in use, even if the main activities moved to the bridge. It was now used to go over the less relevant data or to work on a new projects. "You have no teaching experience to speak of and relating an instinctual knowledge is harder than you think, as you have no doubt experienced. But even if it wasn't, that's no excuse for ditching your work."

"Right, shield watch," Eli looked over at Chloe. "Do you want to continue later or..." he trailed off.

"I'll let you know, okay?" she smiled tightly and he packed up the laptop and headed back to the bridge. Chloe rubbed her hands together, then rocked back and forth on the balls of her feet. She wanted to ask but she wasn't sure how Rush would react. He was usually pleasant to her when they were alone but he had been ticked off by Eli's slacking - even if Chloe had been the one to be blamed for that - and she didn't want to make it worse.

"What is it, Chloe?" he asked without looking up from the console.

"Can I help? With anything?" she blurted out. He raised his head at that and Chloe hurried to explain. "It's just, I would like something to do and I would usually go and help T.J. but the infirmary's almost empty and the inventory is taken so she doesn't need my help with anything and, frankly, I really don't like plants anymore, so hydroponics is out, too."

She didn't add that most of the people on the ship were wary of her and she didn't want to be stared at with suspicion any more than she had to. There was a beep from the other console and Chloe looked at it to see a series of numbers scrolling down.

"The logs of the power reserves data. Take a look and take note of all the changes in the power distribution that have come to pass since our arrival at the ship. Try and find either a pattern or any large jumps, incongruities, things that are out of normal."

"Thanks," she said, receiving only a nod in acknowledgement as Rush went back to his own work.

Several hours later, Chloe's eyes burned and her legs hurt from standing for so long. She had noticed, though, that the power reserves got bigger after every recharge, especially if there had been an opening up of a previously unused section beforehand. She had pointed it out to Rush, who had said it had been to be expected, Destiny compensating for the increasing demands of her crew.

Chloe no longer found it strange to talk about Destiny as a living thing. Too much had happened in the past year or so to be dismissive of the ship's program and mission. Chloe had been surprised to find herself a believer in 'the mission', but for all of the bad things that had happened to her, she also recognized how much she had grown for having gone through them. There was no growth without a pain, it seemed.

"Chloe," Rush spoke to her quietly and she jerked her head up, having been lost in thoughts for some time. "You can go, if you're done."

The thought of going back to her room didn't hold much appeal. She had already spent far too much time inside.

"Don't you need help with anything else?" she asked tentatively. Rush gave her a long look.

"It won't help," he said.

"What?"

"Burying yourself in work to escape from things you don't wanna think about isn't a good or permanent solution," he told her before his mouth twitched in something that might have been a smile. "Trust me on that."

"I know. It's just, people still look at me with suspicion and Matt, well," Chloe sighed. "I still feel hurt over what he did."

"I was under the impression Lieutenant Scott did his best to be supportive of your situation," Rush commented.

"Yeah, he was supportive and optimistic when he visited me. Visited," she emphasized. "I understand that he had duties to carry out, but, I don't know, sometimes it felt like I was just another obligation to him. I don't want to be unfair, I know he was trying and that it was hard for him to see me like that but..." she trailed off awkwardly. "Knowing it doesn't change how lonely I felt at the time."

Rush didn't say anything to that and Chloe was glad for it. He would not be her first choice of a confidante but Eli was too close to her and Matt both and she wouldn't ask him to pick sides. Besides, Rush had a way of making your personal problems seem unimportant in the grand scale of things. Which kind of sucked and made him look like a first-grade bastard with no feelings.

Then again, he had been the only one to tell her to stop pitying herself and try and see the advantages of her situation as compared to everyone else's false assurances that things would somehow work out. And in the end, it had been his idea that led to her being cured.

Rush had been simply too complex to figure out easily. Chloe snorted as a thought occured to her.

"What is it?" he asked. Chloe bit her lip to stop from chuckling. The comparison offered itself too easily.

"Before we started working on derivations, Eli gave me a rundown course on number classes," she started explaining. Rush gave her a half-interested, half-confused look and she continued. "You know, natural numbers, integral numbers, real numbers? Well, I remembered from school that the class of real numbers has some firm rules, like you can't square root a negative number? But Eli said that there is a class of complex numbers where the rule doesn't apply."

"The imaginary unit i being -1 square rooted, yes. A basic math."

Chloe rolled her eyes.

"I wouldn't say basic. Still, it just occured to me that if people were numbers, you would be a complex one."

"Really?" there was an amusement lacing his voice. "Care to explain why?"

"Because normal rules don't apply to you. Or you make them not apply."

"I take that as a compliment."

"Definitely," she grinned.

"And what class of numbers do you belong to?"

"Real numbers with an aspiration of becoming a complex one."

"A worthy ambition," he said teasingly and Chloe laughed. "So tell me, do you have more insight about people's number categories?"

"Well, Eli is a complex number, too, but he thinks himself a real one."

Rush nodded.

"He's still wary of applying his full potential," he agreed. Chloe leaned against her console, thinking over the other people on the ship.

"I think most of the people would be rational or even real numbers, in that they are held back by the general rules and never trying to reach beyond. But some are even more constrained."

"Colonel Young, for example?" Rush suggested and Chloe giggled. "Now, he's definitely a perfect example of an integer number thinking himself a complex one."

Chloe burst out laughing.

"You are biased," she accused playfully and Rush shrugged.

"We all have our faults, Chloe," he said but there was a smile on his face, too. She was still laughing when the door hissed open and Adam Brody walked in, pausing at the sight of the two of them.

"Hey," he greeted. "What's so funny?"

"Mathematics," Rush said in a deadpan voice which prompted a new round of giggles from Chloe. Brody looked between the two of them before shrugging it off and walking over to Chloe's console.

"Are you finished?" he asked and Chloe nodded, shutting down the logs she had been looking over.

"All yours," she stepped away from the console. Brody waited for a moment longer before taking her place and Chloe frowned. He was wary of her, too. She looked over at Rush who was watching it all with a blank face. Her good mood evaporating, she made to leave the room and go back to her quarters, to spend another night alone.

"Chloe?" Rush said quietly and she looked at him. "I was working on some calculations in the corridor, if you want to have a look. The code is still the same."

"Thanks," she replied, smiling a little. "I think I'll check it out."

It was like and yet unlike her previous blackouts. One moment she was standing before the wall where Rush's calculations ended, the next she was writing down furiously the numbers and symbols from her mind. There was a certain beauty in the equations she was producing, the elegant simplicity of order and rules. Chloe hadn't been much of a math lover during her years as a high school student, even if the dislike had stemmed more from the fact that unless you had been a geek, math had not been supposed to be liked, rather than because of the subject itself.

Later, the only math she had needed in her political studies had been statistics. Derivations, integrals, complex numbers, those had been for the natural sciences' students, not Chloe Armstrong, the senator's daughter who had been getting ready to walk in her father's footsteps.

Her stay on Destiny had changed that. She could have played the role she had been trained for, sure, but with her father gone, what would have been the point? The blue aliens and the changes they had wrought in her brain had chosen a different course for her and for now, she was willing to give it a try. After all, there were enough players in the political game onboard but only she was able to make FTL jumps calculations in her head.

The door to the corridor hissed open as she contemplated her work so far. Rush walked in, not in the least surprised to see her there.

"Keeping busy?" he asked as he came to stand next to her, studying the writing she had done.

"It's a way to pass time," she replied, shrugging. "What do you think?"

"It's amazing," he said in the same tone he had when looking at her work in the infirmary. He reached out to trace some symbols and added quietly. "It's perfect."

Chloe looked down, suddenly shy. Rush was spare with his praise, everyone knew that. Even Eli had to work hard to earn even a grudging nod from him. So what made her special?

"It's not really me," she spoke hesitantly. "It's whatever they did to me."

"I had a teacher in my first year in Oxford," Rush said equally quietly. "She used to tell us at the end of every lecture that as long as we put in our best efforts, we'd be able to learn anything, regardless of any innate talent or lack of it. Except for singing because the shape of the vocal chords is what's important there."

Chloe turned her head to face him. He wasn't looking at her, still staring at her equations.

"What does that mean for me?"

"The aliens might have jumpstarted your brain but the choice to use what you gained was your own doing. After you were cured, you could've chosen not to pry into what was left of your skills. Why did you?"

"I told you, I wanted to be useful."

"And?"

Chloe bit her lip. Was there another reason for her to try and see how much she had retained of her knowledge? Yes, there was.

"I felt they owed me something for what they did to me. After what I went through, I deserved something good to happen to me. This ability," she gestured at the wall. "It makes me special. I like being special," she admitted. Rush looked at her sharply.

"Chloe, you have always been special," he scolded her.

"Not when compared to you or Eli or the other people onboard. I was the least prepared of all, contributed almost nothing to the mission. I was a burden. Now I'm not. It's as simple as that."

He remained silent, watching her. She held his gaze, not initimidated by him as the other people on the ship seemed to be. He looked away first, clearing his throat.

"You should go and get some rest. It's late and Lieutenant Scott will worry about you."

"He won't," she said with conviction. "I have yet to move back with him," she explained.

"He can't be very happy about that," Rush remarked in a neutral tone. Chloe shrugged.

"He pulled away first. He wouldn't be with me even when it was clear I wasn't contagious. I love him but I'm not sure if I'm in love with him. Does that make sense?"

"A little," he assured her. "Certainly more sense than you confiding in me," he added in an obvious attempt to lighten the mood.

"I wouldn't say that. We shared secrets before, didn't we?"

"Aye, we did."

The silence stretched between them, familiar and comfortable. They understood each other well, Chloe realized. Their pasts, their age difference, their at times conflicting opinions, they didn't mean much in the context of the bigger picture. Kindred souls, she thought it was called. Or maybe two complex numbers in the midst of real ones.

"Nicholas?" she asked, realizing that she had never before called him that. He was Rush when she talked to other people and when they were alone, she simply eschewed any distinction beyond you.

"Yes?" he sounded a bit perplexed at her form of address but Chloe didn't care for his confusion. Their height close enough so she didn't have to stand on her toes, she took a hold of his face and decisively pressed her lips against his. He didn't react beyond a quick intake of breath and Chloe pulled away after a few seconds of contact.

"Is this okay?" she asked.

"It could complicate things," he said and well, it wasn't an outright denial.

"Things have been complicated for months," she pointed out. "This is simple in comparison."

"I guess it is," he agreed and she leaned in to kiss him again. He returned the kiss this time, opening his mouth to her as he pulled her closer until she was plastered against him. One of his hands was splayed across her lower back, the other holding the back of her head, his fingers entangled in her hair. Chloe wound her arms around his neck, the thrill of being physically close to another person after her long isolation almost intoxicating.

"Shall we move?" his voice was wonderfully rough against her ear and Chloe ground her hips against his in approval.

"No," she breathed out as he tilted her head back so he could nip his way down her jaw and throat towards her collarbone, his beard providing an unfamiliar but not unwelcome scratching against her skin. "It's fitting to do it here."

She felt his mouth curve in a smirk against her skin and then he was tugging at the bottom of her top, his thumbs pressing against her sides as he dragged it up and off. She did the same to him, the layers of his clothes more numerous than hers. He was thin, she noticed as her hands grazed against his ribs, each one prominent enough that she could count them all. He neglected himself to work on the ship, she knew that much even before but only now as they were getting naked did she realize just how much it was.

If he took note of her sudden concern, he said nothing, cupping one of her breasts in his hand instead, grazing his work-roughened thumb across the nipple until it was stiff and taut and then did the same to the other. Rush, no, Nicholas, was almost casual in the speed and efficiency with which he caressed her. Then again, he had years of experience on her and anyone capable of his focus had a potential of being a great lover.

They were both relatively quiet as their took off each other's clothes, only their panting breaths and an occasional moan disturbing the silence of the corridor. It wasn't the need for secrecy, not exactly. It was more like any words between them were superfluous and uneeded. She had no need to ask for more pressure of his fingers on her clit when the arching of her back spoke clearly. And he didn't need to tell her to hold onto him as he backed her into the wall that had yet to be written upon, their clothes and shoes discarded carelessly to the ground.

She was flexible from her yoga exercises and it was easy to cross her ankles behind his back as he sank into her, urging him on as he started moving at a tempo that was too slow for her taste. She felt him grin into her neck as her legs tightened around his waist and she yelped when he playfully pinched her ass, rubbing the sting afterwards.

"No need to hurry," he murmured and slowed down even more, his thrusts measured and deep and Chloe rolled her head back, giving up the control to him. The cold of the metal wall at her back helped her to stay grounded, the chills a pleasant counterpoint to the heat in her lower body. Nicholas suddenly pulled her closer, transferring more of their shared weight to the wall. She wondered at that until he pushed his right hand between her legs, working his talented fingers against her clit. She didn't realize how close to a climax she had already been and she came with a gasp, her back arching, pressing her upper body tighter against her lover.

He stopped moving while she shook in her orgasm, a pleased smirk on his face.

"One more for the road?"

And she could have killed him for that sentence alone but his accent was thicker than she ever heard, the Rs resonating throughout her body down between her legs and she only nodded, biting at her lip as he started moving, faster than before but no less in control. She clutched at his shoulders and buried her head against his neck, her hips bucking almost of their own volition.

It didn't take long for him to reach the point she was familiar with, his hands digging into her hips almost painfully and his thrusts hard and fast. She wasn't sure if she would come close before or after him - she knew better than to believe in simultaneous orgasms during the first time - but he was obviously thinking of her and moved his hand off her hip to once again tend to her clit.

"Is it safe inside?" Nicholas growled into her ear and it took her a moment to comprehend what he was asking and then she nodded, breathing out "Yes", tightening her grip on him as his thrusts grew erratic and desperate and then he pressed into her and stilled, a low groan escaping him as he squeezed his eyes shut and it was worth losing an orgasm to see him so undone.

They sank to the ground together, him taking the weight as she sprawled across him while they caught their breaths. He was still in her, though and Chloe didn't mind in the least, even if she was sweaty and sticky and disheveled.

He pushed her hair from her face, smiling at her and she grinned back, suddenly elated.

"Thanks," she said. His mouth quirked in that smirk she was coming to recognize as pleased.

"I would say anytime but I don't wish to be presumptuous."

She laughed giddily, the aftermath making her feel happy and careless.

"Presume away," she told him and pulled him into another kiss. There would be trouble with this, she wasn't so naive as to think any different, but she deserved this after everything. After all, she was a complex number, not bound by the normal rules.