Title: The Spirit of Evolution.
Pairing: Morgan/Reid
Rated: FRAO/NC-17/Rated M
Summary: Morgan wonders about the change in Spencer. Pure, shameless smut. This takes place in season 7.
A/N: So apparently, once you write Bottom!Morgan once, you can't stop :P Anyway, I should warn you that I have little experience with writing M/R outside the context of a prompt so, since this came from my own imagination, it contains little but smut. If you have an ounce of tameness in your soul, you shouldn't continue. Seriously, this is the dirtiest thing I've ever written and I write a lotof smut.

Any other time, Derek would have found the two of them, tripping over their own feet while pulling at each others clothes, incredibly funny. Right now though, he was just too damn horny to give it a thought. He really didn't know what had gotten into him lately, he shouldn't be this aroused after the night before, hell he was surprised his lover could actually walk normally. It had been going on for a few months now, getting more and more intense and the only explanation he could come up with was something about Spencer had changed. Though he couldn't place it. All he knew was that it caused something in Derek to crave his lover.

All the time.

As Spencer pulled him down on the bed to lay across his body, Derek gave up thinking about it and kissed his lover as hard as he could without hurting him. Their tongues tangled for a few long minuted while their bodies moved together, hips circling and rubbing hard cocks together creating such sweet friction that Derek was sure he could cum from this alone. After a short while and a few missing buttons later they where naked and stroking one another.

"God, I need you now Derek." Spencer moaned against his ear as he reached out to the bedside table to retrieve the lube and handed it to him. Morgan opened the lid, squeezed some out and pressed a finger to his lover's entrance. When he heard Spencer hiss sharply he moved to look, he always loved seeing desire burn in his eyes. However he found only a pained expression gracing his features.

"Spence, Baby?" He asked concerned, instantly moving away. Spencer tried to pull him back but he refused to be drawn back.

"I'm fine, just a little sore from last night." He assured, sitting up and kissing Derek passionately, "Don't stop." He whispered against his lips.

"Okay," Derek replied, kissing back, "Take me."

Spencer let out a little groan, "I wanted you inside me." Protesting even as he grabbed the lube while Derek flipped over onto his hands and knee's. He knew that Spencer knew he wouldn't relent.

Derek smirked back at him, licking his lips as he watched Spencer spread lube over his fingers, "Seems like you've had a little too much of that."

The last word was more of a moan as a finger rubbed a circle around his entrance before gently pressing in. Morgan always liked looking his lover in the eyes as they made love but, truthfully, he much preferred this position.

"Oooh, oh yeah." he moaned as his eyes fell shut and his head fell forward, resting his forehead on the pillow.

"You like that?" Spencer whispered, leaning down to lick across Derek's neck. He trailed his tongue around his shoulder before stopping to suck low, leaving a mark.

Panting when Spencer slowly added a second finger he answered in a breathy tone, "Yeah. Yeah. Fuck."

Spence was now tweaking his nipple with his free hand and Derek felt the anticipated sensation coming.

The feeling of being lost in the moment of arousal, of knowing nothing of the world beyond this bed and this man and this passion. He clenched his eyes closed and welcomed it, needed it.

Though it could be luck, he couldn't rule out Spencer's intuitive genius as the reason it was at that moment he curled his fingers and pressed firmly against Derek's prostate. He cried out, completely without shame, as the world fell away.

Spencer took his cue and added in a third finger, but after only a few seconds it was enough, and Derek was making a rather un-seemly whining sound. Holding out for a few more strokes, Spencer finally gave in and moved to kneel behind him, kissing his shoulder blades as he spread lube along his shaft.

After entirely too long, Spencer finally pressed the warm head against him before entering slowly. They'd been together two years, they hadn't needed protection for a long time.

After pausing a moment, Spencer started moving, gasping as he did so and Derek could feel a tremor pass through the other mans body.

Spencer was often, by his own insistence, the one being fucked but Derek often thought it was due to the Doctor somehow forgetting how much he loved topping because, in all honestly, Derek never saw reactions from Reid like his did at times like this.

"Ahh, so fucking tight." He heard his lover breath as long, still lubed fingers spread his ass cheeks wide, exposing him fully, "So good."

"Yeah." Derek breathed in reply, god it made him hot when Spencer was like this.

When the thrusts sped up, Derek lowered himself to rest on his forearms and made breathy moans with every thrust. He could barely catch his breath and he didn't even care, he was pushing his hips back into Spencer over and over. He almost lost it when he, hand to god, heard the man behind him growl. Fuck that was sexy as hell.

"Spencer." He murmured, caught up in the feel of him.

Grasping the skin of Derek's hips with bruising force, Spencer breathed, "Yeah." and thrust harder, before lifting a hand to slowly trail his nails down Derek's back. Not enough to hurt, but enough to make his entire body tremble. He pressed his face into the pillow as he felt the tension building. He desperately needed release but Spencer still hadn't paid any attention to his throbbing cock.

Spencer was now thrusting into Derek so hard the bed was creaking with the movements and it was incredible. But it was not enough.

"Spence baby, please." Was all he could muster at the moment. His entire body was coated in a fine sheen of sweat and his skin felt like it was on fire.

Squeezing Derek's ass cheeks, digging his nails in, Spencer grunted, "What?"

Making a sound somewhere between a scoff and a sob, Derek repeated, "Please."

He felt Spencer lower himself to cover Morgan's upper body with his own, still managing to thrust shallowly, and gasped as his lover bit the curve of his shoulder, "Tell me what you want Derek."

Panting into the pillow, made damp by the perspiration pouring from him, he gasped, "Touch me, make me cum. Please."

"Good boy." Spencer rasped before raising again and resuming his furious thrusts. Derek moaned loudly when a firm grasp took hold of his neglected cock and he almost lost it right then.

"Cum Derek." His lover said and finally everything became too much to bear and he came. Hard.

He threw his head back and screamed. He actually screamed. The air around him seemed to electrify and crackle before blurring and finally turning black.

Somewhere in the back of his mind he heard Spencer release a cry of his own, felt warm fluid filling him but the next thing he consciously knew was being laid on his stomach on the bed, looking at a concerned Spencer.

"Did you pass out? Are you okay?" He asked, worry dripping from his tone.

Derek took a second to analyze the situation before chuckling when he realized that, yes, he had passed out.

"Baby boy, you fucked me into unconsciousness." He choked out, laughing into the pillow. It was so beautifully absurd that one could actually faint from sex.

Mind blowingly amazing sex. But still. Sex? Really?

Spencer however, still had a frown marring his brow, "You should tell a doctor."

"I'm gonna tell everyone." Derek murmured in response and finally Spencer let out a slight chuckle.

Settling on his side, resting his head on his folded arm Spencer narrowed his eyes exaggeratedly, "You'd better not."

After a few more moments of laughter, they settled in each others arms and Derek's mind drifted back to his earlier thoughts, about something having changed within Spencer. He watched the other man, his eyes closed, falling asleep, ghost of a smile still there. He looked like the same old Spencer. Except ..

There was something. His features seemed more defined than the soft lines of before. His hair was a lot longer than it had ever been before and it seemed to draw attention to his much broader frame. Still skinny but much more to it than there had been.

Then there was tonight. His actions and personality had been a lot more assertive lately, both with him and others. He'd never been weak in the slightest, but he was something else entirely now. He seemed a lot more ...

With a stark clarity, it hit him and Derek was left wondering when exactly Spencer had become a self-assured, confident and slightly dominant kind of man.

Derek didn't even try to fight the smile that bloomed on his face when he realized the answer.

It had been about two years ago.

End.