Derek groaned as his boyfriend squirmed on his lap. God, did Spencer have any idea how hot he was? At work he walked around in his sweaters and dress pants that showed just how delicious his ass was, not knowing just how much it drove Derek crazy, how it made him want to pull those clothes off and slam him down on the nearest table and make him writhe in pleasure. It had been maddening before he and Spencer had begun dating, but at least at this point he could do so at home in the evenings, just as he was doing now. He moved a hand up to Spencer's hair and tugged it back, firm enough to be demanding, but not enough to hurt. His lips made their way to the pale neck, and began to softly lick and nip. He briefly remembered how much he liked seeing his Pretty Boy in scarves, and made the choice to begin sucking in earnest, leaving blossoms of purple on the pale skin between licks and nips that grew progressively harder. He couldn't help but smirk at the moans that came out of that beautiful mouth at his own mouth's ministrations, though his smirk was replaced by a moan of his own as one of his well-placed hickeys caused Spencer to grind his hips down hard, providing delicious stimulation on his already-present hard on. Soon the kissing was taken over by grinding, as they both sought more pleasure. When Derek's head fell back, completely overwhelmed by the friction on his dick, he felt kisses on his neck, followed by a few well-placed bites that caused his hips to buck up without his permission.
Knowing that he couldn't last much longer like this, he picked up the smaller man, who grinned widely, and began to walk to the bed, whispering dirty words in Spencer's ear, telling him just how much he'd wanted him, daydreamed about pushing him down on tables at work.
He was met with a mischievous grin before Spencer whispered in his ear, voice wracked with desire, "Don't you have a kitchen table?"
Oh, fuck yes.
He turned into the kitchen, barely able to carry Spencer and himself fast enough, and quickly laid him down on the table. His hands roamed under the sweater vest that Spencer had worn to work and therapy today. He felt the hipbones, soft trail of hair, and expanse of chest that was his to explore as the man beneath him writhed. He made quick work of removing the sweater vest before slowing down to appreciate the sight beneath him. The slim man beneath him was panting breaths out through his pink and recently kissed lips, moving without even being touched, eyes full of desire for Derek alone. His soft hair was out of place from being pulled earlier. His skin was pale, though not pallid, and it fit with his complexion. His hipbones stuck out as he lay on his back, and between them a soft trail of hair led to his obviously straining erection. On his neck were a series of fresh purple bruises, Derek's mark. The best part? The man beneath him had told Derek that he loved him today, and the love that welled up in Derek's heart at that meant far more than how sexy he looked right now. Though, he wasn't complaining, and the sight was fucking beautiful.
He stepped between Spencer's legs where they hung off the table and pulled him forward so that their dicks were rubbing each other through their pants. When Spencer began moving his hips Derek got a mischievous grin, and took a firm grip on his hipbones, holding his hips down against the table, so that only he could control the friction. When he realized this, Spencer whimpered and arched his back, which was met by Derek leaning down to lick around his nipples. After licking each of them softly for a few minutes, drawing mewls of pleasure from the recipient, Derek bit down softly on one, causing the man a sharp intake of breath and a twitch in his cock, eliciting a grin from Derek. Maybe they could explore this later, but fuck, his cock was so hard that it almost hurt.
He moved his hands down to snag Spencer's dress pants and pull them off, leaving the man completely naked and spread out on a table for him beautifully. He made quick work of removing his own clothes, disappearing for only a second to grab the lube from his bedside drawer. When he returned he was met with a sight that made him gasp and almost drop the lube. Spencer had changed positions and was now bent over the table, ass facing Derek, legs spread, ready for prep. Fuck, that was hot. He stepped forward and traced a finger down Spencer's spine, drawing a shiver. "You want me to prep you, baby?" Derek knew that Spencer wouldn't be in this position if he didn't, but consent was something that, given his personal experiences, he took very seriously. When Spencer nodded Derek poured lube onto his index finger and slowly circled it around the pink hole. When Spencer leaned back for more, Derek pushed harder and began to work his finger in. He always took his time with the prep, mostly because he didn't want to cause Spencer any pain, but he also had to admit that he didn't mind watching Spencer writhe in pleasure from just one finger, knowing that soon his rather large cock would be in the same tight hole.
After he felt that Spencer had loosened a bit he slipped in another finger, eliciting a small gasp. "You okay, Spence?" he asked before moving his fingers. "Yeah" the breathless voice answered, "'s good. Don't stop." Reassured, Derek began to slowly move his fingers, scissoring them and curling to touch the spot that made the body beneath him jump and arch in pleasure.
After a few minutes he asked, "Do you want a third finger?

"Mmm, no. I wanna feel your cock stretching me" Spencer practically purred, still moving his hips in an obscene fashion, and, fuck, how could he say no to that?
He poured more lube onto his dick, coating it liberally, before he lined himself up with Spencer's ass. He took a firm grip on the wriggling hips and began to press the head in. He heard a gasp as the head finally pushed in. He stopped for a minute to rub Reid's back softly to give him time to accommodate the intrusion.
After a second the hips were wriggling again, and he heard, "C'mon Derek. Fuck. Fuck me... not that fragile... not gonna hurt me."
With the encouragement he pushed deeper until he was buried all the way into the tight ass, not able to stifle the moan that escaped his lips as his hips met Spencer's ass.
Slowly he pulled out and pushed in again, letting the writhing of Spencer's hips set a pace that began to pick up.
He moved his own hips, trying to find the sweet spot, and knew he'd succeeded when he heard a sharp intake of breath and felt the already tight hole enveloping his dick clench even tighter.
"Oh... fuck... right there, harder, fuuuuck."
It wasn't often that Spencer Reid's vocabulary was reduced to such simple words, and Derek considered it a personal accomplishment to do so.
He reached around to grasp the man's hard cock and stroke it in time with his own increasing thrusts, lost in his own pleasure and the moans of the other man. At some point he licked and nipped at Spencer's neck, enjoying the way his hips bucked even harder at that.
Eventually, after how long he wasn't sure: time didn't exist in this sea of pleasure, he felt his own balls begin to tighten.
"Gonna come, Spence."
"I'm so close too. So clo- Oh god"
With that the hole around him clenched and Spencer's head fell back, his breathing even harder than it had been moments before.
The sight was enough to push Derek over the edge and before he knew it he was coming inside Spencer's ass, harder than he had in a long time.