Fic: I just don't get it - evolutionarily, I mean
Title: I just don't get it - evolutionarily, I mean (Chapter 3/4)
Author: celtic_forest
Pairing: Sam/Dean
Rating: NC-17
Length: 2,446 this chapter
Beta thanks to epicycles
A/N: I own nothing but a mortgage. Not my boys, just my toys.
Chapter 1: I just don't get it
Chapter 2: About last night…
"Sammy…"
"Keep your shirt on, I haven't figured this out yet. Or, you know, not keeping it on is good too."
"Smart ass. In every sense of the term." Teasing his brother brought out a flash in Dean's eyes. "Like, you're a sarcastic bitch; you're smart but you're an ass; and, judging from the way you waddled in here, it still smarts from last night." Dean grinned.
"Or if we were English it'd be a compliment on how it looks in these jeans," Sam added, with a demonstrative wiggle he immediately regretted.
"Right-o, old chap."
Sam kept typing on the library computer, eyes scanning the screen. After another round of crumpling papers from the recycle bin and tossing them back in from across the room, Dean peeled off his shirt and threw it at Sam.
"Hey!"
"You said I could, bitch."
"Jerk," Sam sighed, turning to look at Dean. And look some more. "Ok, I'm good with that."
"Can we get lunch sometime this century?"
"Yeah, I've downloaded all the papers I can find. I can work on this from the laptop now." As Sam removed his jump drive, Dean looked at him in confusion.
"You were downloading whole newspapers?"
"No, papers. Research articles published in academic journals. Mostly on the interactions between natural selection, sexual behavior, and anatomy."
Dean had tuned him out, as the second part of what he'd said before seeped in. "You're not satisfied yet? You're still going to work on this, on the laptop, for no particular reason?"
"I told you, I just don't get it. Why should there be a bundle of nerves right there, that makes anal sex feel so good? It doesn't make any sense - evolutionarily, I mean."
Dean's head hit the desk with a thunk, and the wood muffled his words but not his exasperation. "You have to research it? You can't just enjoy it?"
"I can multi-task." Tossing Dean's shirt at him, Sam said, "Let's go eat."
~~<>~~
In the car, Dean ventured, "So, you're researching the evolution of homosexuality? Being gay can't evolve, people just do it." In school, Dean's ears had perked up whenever reproduction was discussed, so he had a vague idea of evolutionary theory.
"That's not exactly what I'm researching, and it's a popular fallacy that there's necessarily a negative correlation between homosexual behavior and long-term reproductive success. Homosexuality could be a product of natural selection. Also, it's really common with animals."
"Dude!"
"Not people with animals! Among animals. As in, the behavior occurs in many species."
"I did not need to know that."
"Besides, exclusive homosexual behavior is even less common than homosexual orientation."
"In English, Sammy."
"Most gay men have sex with women at some point in their lives, and a lot of gay men have kids.
"Plus, it's not like behaviors are simple, or are due to single genes. There could be multiple traits that are each evolutionarily beneficial for a variety of reasons, but if all are combined, they result in homosexual orientation."
"Or, if women think a guy's gay, they can't wait to jump him."
"For example."
Dean was doing his best to derail Sam's train of thought, since it had left his station a while back. Meanwhile, Sam was pleased to be able to have a two-way conversation on his current research, but he wasn't surprised Dean would pick a crude (though apt) example.
When Sam smiled at him, Dean looked at his dimples with narrowed, suspicious eyes. He hated it when Sam made fun of him and he didn't get the joke. He could still retaliate, though.
They were coming up on a drive-thru.
"Hey Sammy," Dean said, while trailing his finger down Sam's chest and over his stomach, Sam's abdominal muscles fluttering under the light touch, "this is kind of cool. Tell me more." Dean flicked open the top button on Sam's jeans and started to pull the zipper down slowly, tick by tick.
"Uh," Sam said, looking confused. "Well, another idea is, if a person who doesn't have their own kids to take care of ung." Dean had finished with his zipper and pulled Sam's half-hard dick out of his boxers.
"Go on."
"Um, if they help out with their nieces and nephews a lot insteeeahd..." Dean stroked Sam to full size.
"Yeah?"
"Then the person still passes on their genes, god, Dean, wha..?"
Dean traced a finger up the underside of Sam's erection, to the vein under the tip. Gently rubbing the spot, he said, "what were you saying?"
"It's called k-kin selection," Sam panted, and ran a hand through his hair.
"Hmm. What's that?" Dean slid his finger back down, stroked across Sam's balls, then gave a long pull up, ending with his thumb brushing over the tip.
"It's a, ahhuug, a whole big thing."
"You know, Sammy…" Dean squeezed, and pre-come obediently popped up.
God, Sam thought, why was Dean still talking? And expecting him to have an actual conversation? Confusion and pleasure swirled in his mind.
"I've noticed," Dean continued, "a 'negative correlation'" he caught Sam's eye and licked his hand wetly, eliciting a groan from his brother. Dean caressed the top of Sam's penis, collecting the pre-come gathered there, then slid his hand down the length. Sam closed his eyes and threw his head back hard, striking the car window and edge of the door but not seeming to notice. "Between the size of your cock" he pulled up and twisted "and the size of your words."
As Dean pumped up and down, he rolled his window down and a voice crackled through a speaker: "Welcome to Burgertime, can I take your order?"
"I'll have a bacon double cheeseburger, large fries, and chocolate shake. Sam, what're you getting?" Dean asked sweetly, and flicked his slit.
"AH, gaa, nugh!"
Crackle: "What was that? Please repeat your order."
"He said combo number nine."
Crackle: "Uh huh. Second window." Click.
"D-Dean…" Sam didn't have a follow-up to that. The fact that they were in the middle of a drive-thru had penetrated the fog in his brain, and he wanted to tell Dean to stop, but on the other hand, not.
Dean used his other hand to play with Sam's balls, gently juggling them with his fingers. He moved the Impala up in line, as the people at the window exchanged cash for a greasy white bag.
Feeling the car move, Sam gasped, "Dean!"
"Your vocabulary is suddenly really limited, Sammy, are you ok?" Dean pumped Sam's shaft with one hand, while he spiraled a finger around the tip, then rubbed the soft pad of his finger back and forth across the wet slit.
"Fuck - (gasp) - er!"
Dean started to pull the car forward again, and pulled on Sam hard, twist, down, pull.
"God, oh god, Dean!" Sam's come spurted all over his shirt, with a drop landing on his chin.
Dean stopped the car, leaned out the window, and grinned. "Darlin', I think we're gonna need some extra napkins with that."
~~<>~~
They ate lunch at a picnic table, watching the kids on the playground equipment and a jogger running in circles on the path around the small park.
"Dean, I can't believe you ordered me the fish sandwich combination."
"Hey, you ordered number nine. I believe your exact pronunciation was 'nugh.' Besides, you're a health nut and fish is healthy."
"Not deep fried reconstituted fish-bits slathered with tarter sauce!"
"I don't see you scraping off the tarter sauce."
"That's the good part. And it's not the point, Dean. I didn't say 'nugh' and it didn't mean nine."
"Oh yeah? What did it mean?" Dean waggled his eyebrows at Sam. "Was it part of your big evolutionary theory of gay sex? 'Cause you weren't making much sense at the end of that explanation." Dean's eyes sparkled with laughter.
Sam wanted to be irritated, but just grinned, because his brother was so goddamn gorgeous (how had he never noticed that before a couple of days ago?), and had just given him a hand job. In the middle of a drive-thru. Irritated after all, Sam said, "it's not my theory, and the point I'm trying to get at is much more specific anyway."
Dean slurped the last of his milkshake and licked his lips. As Sam's eyes followed Dean's tongue around those full lips, he suddenly felt a lot more charitable. "If you find us some privacy, I'll give you a demonstration." He held Dean's eyes and ran his tongue over his own lips, making his meaning clear.
They jumped up to clean the table and toss their trash, got to the car and, after a bit of impatient driving, found a wooded two-track. There had been a chain across it, but the thin latch had rusted through and the chain had fallen. The track curved, and ended in a clearing. Judging by the detritus on the ground, they weren't the first lucky couple to find this spot. They just had to hope a visit by a random patrol car wasn't as likely during the day as it would be on a Friday night.
Sam leaned across the seat and kissed Dean, long and slow and full of promise. When he got out of the car, Dean followed. Sam curved his arms around Dean's back, lowered them to his ass, and pulled their hips together. He traced the outer curve of Dean's ear with his tongue and whispered, "Get on the hood."
Dean's pupils were wide and his eyes already beginning to glaze as he complied. Sam pulled his own shirt over his head then took off Dean's. Sam's muscles rippled as he ran his hands over the only body he knew as well as his own. He stepped in for a kiss, and Dean spread his knees to let him come close. Sam's hands traveled down Dean's chest, paused to gently pinch his nipples to hardness, and continued over his stomach to the waistband of his jeans. His fingers dipped inside as Dean pressed his mouth to Sam's, thrusting his tongue in and out until Sam moaned.
Coming up for air, Dean gasped, "So what is this demonstration for? Not that I'm complaining so far."
"Shut up, I'll explain later." Sam unbuttoned Dean's jeans and lowered the zipper, thinking, this made twice in one day Dean wanted to talk during sex more than he did. He'd smirk if he weren't more interested in the light taste of salt on Dean's collarbone.
Sam tugged at Dean's jeans and boxers. Dean put his arms out behind him on the hood and leaned back, lifting his hips so Sam could pull the clothes down. After kissing his way down Dean's body, he took the head of Dean's cock in his mouth and sucked. Dean would deny the whimper that escaped him. Sam's tongue lazily circled the tip and he tasted pre-come for the first time. The newness of the taste, and of the experience, exploded in his mouth. He looked up to find Dean watching him with love as well as want in his eyes, and Sam felt his heart lurch.
Long licks left Dean's erection slick, and Sam slid his lips down, down. He consciously relaxed his gag reflex and took Dean nearly all the way in. Dean may have the gorgeous lips, but Sam had the large mouth in the family. He was too distracted experimenting with his tongue to imagine how Dean would reply if he heard Sam admit to having a big mouth, although judging by the sounds he was making now, Dean had no complaints. Sam managed to move up and down a few times with Dean deep inside his throat, before he had to pull up. He let his saliva run down, lubricating his hand as it took his mouth's place.
With a hand under Sam's chin, Dean pulled him up and into a kiss. He was surprised to hear himself murmur, "love you" against his brother's lips. He gasped as Sam twisted his hand around the head of his cock. When he felt Sam's breath tickle inside his ear with a whispered "I'm yours," Dean arched his back and came. Sam's arm was already around his back, lowering Dean to the warm hood as he panted, weak and spent. Sam's head rested in the hollow between his shoulder and neck for a while, then Sam disappeared to rustle around inside the car.
When he came up with some of the extra napkins from Burgertime, they both laughed.
~~<>~~
Sam was driving because Dean was too tired now, and he was talking because he apparently wanted to torture Dean.
"So, the point was, you went through all the stages of physiology and behavior without any feedback between the nerve bundles around your prostate and your conscious mind. The blood vessels in your penis dilated, your ejaculatory ducts opened, "
"What the hell are you talking about?" Dean felt free to interrupt because, for some reason, they were talking about his very personal anatomy.
"You got hard and you came."
"I noticed. Why the re-cap?"
"Because your body did everything physiologically necessary to impregnate a woman, "
"Were you and I at the same blow job?"
"without stimulation of the prostate."
"So?" Dean asked, then mentally kicked himself for encouraging the lecture.
"So, the reason anal sex feels so good, or at least one of the reasons, is because the prostate is stimulated through the rectal wall. The reason rubbing the prostate feels good is because it's surrounded by sensitive nerve bundles that send feedback to the brain."
"Ok, Sherlock, mystery solved, now shut up."
"But a lot of the body's physiological actions are coordinated by nerves and the subconscious brain, including, for example, dilation of blood vessels and opening and closing ducts."
"I hate you."
"You do not, you love me." Sam flushed and ducked his head, but went on. "The way nerves communicate with the brain is very precise, not just a random accident. So we have to figure out why a nerve pathway evolved that contributes to gay sex but isn't necessary for procreative sex."
They do? "We do not. Now shut your cakehole."
"I have a theory."
"Bunnies or midgets?"
"I just have to look at that research again when we stop for the night," Sam added, stepping harder on the accelerator.
Dean wished they hadn't gotten started on this in the first place. Mental pause. Except that it started because he'd fucked Sam and Sam had loved it. Small price to pay…
"Does this mean we get to experiment?"
Sam flashed him a grin. "You always were more into fieldwork than library research…"
Author: celtic_forest
Pairing: Sam/Dean
Rating: NC-17
Length: 2,446 this chapter
Beta thanks to epicycles
A/N: I own nothing but a mortgage. Not my boys, just my toys.
Chapter 1: I just don't get it
Chapter 2: About last night…
"Sammy…"
"Keep your shirt on, I haven't figured this out yet. Or, you know, not keeping it on is good too."
"Smart ass. In every sense of the term." Teasing his brother brought out a flash in Dean's eyes. "Like, you're a sarcastic bitch; you're smart but you're an ass; and, judging from the way you waddled in here, it still smarts from last night." Dean grinned.
"Or if we were English it'd be a compliment on how it looks in these jeans," Sam added, with a demonstrative wiggle he immediately regretted.
"Right-o, old chap."
Sam kept typing on the library computer, eyes scanning the screen. After another round of crumpling papers from the recycle bin and tossing them back in from across the room, Dean peeled off his shirt and threw it at Sam.
"Hey!"
"You said I could, bitch."
"Jerk," Sam sighed, turning to look at Dean. And look some more. "Ok, I'm good with that."
"Can we get lunch sometime this century?"
"Yeah, I've downloaded all the papers I can find. I can work on this from the laptop now." As Sam removed his jump drive, Dean looked at him in confusion.
"You were downloading whole newspapers?"
"No, papers. Research articles published in academic journals. Mostly on the interactions between natural selection, sexual behavior, and anatomy."
Dean had tuned him out, as the second part of what he'd said before seeped in. "You're not satisfied yet? You're still going to work on this, on the laptop, for no particular reason?"
"I told you, I just don't get it. Why should there be a bundle of nerves right there, that makes anal sex feel so good? It doesn't make any sense - evolutionarily, I mean."
Dean's head hit the desk with a thunk, and the wood muffled his words but not his exasperation. "You have to research it? You can't just enjoy it?"
"I can multi-task." Tossing Dean's shirt at him, Sam said, "Let's go eat."
~~<>~~
In the car, Dean ventured, "So, you're researching the evolution of homosexuality? Being gay can't evolve, people just do it." In school, Dean's ears had perked up whenever reproduction was discussed, so he had a vague idea of evolutionary theory.
"That's not exactly what I'm researching, and it's a popular fallacy that there's necessarily a negative correlation between homosexual behavior and long-term reproductive success. Homosexuality could be a product of natural selection. Also, it's really common with animals."
"Dude!"
"Not people with animals! Among animals. As in, the behavior occurs in many species."
"I did not need to know that."
"Besides, exclusive homosexual behavior is even less common than homosexual orientation."
"In English, Sammy."
"Most gay men have sex with women at some point in their lives, and a lot of gay men have kids.
"Plus, it's not like behaviors are simple, or are due to single genes. There could be multiple traits that are each evolutionarily beneficial for a variety of reasons, but if all are combined, they result in homosexual orientation."
"Or, if women think a guy's gay, they can't wait to jump him."
"For example."
Dean was doing his best to derail Sam's train of thought, since it had left his station a while back. Meanwhile, Sam was pleased to be able to have a two-way conversation on his current research, but he wasn't surprised Dean would pick a crude (though apt) example.
When Sam smiled at him, Dean looked at his dimples with narrowed, suspicious eyes. He hated it when Sam made fun of him and he didn't get the joke. He could still retaliate, though.
They were coming up on a drive-thru.
"Hey Sammy," Dean said, while trailing his finger down Sam's chest and over his stomach, Sam's abdominal muscles fluttering under the light touch, "this is kind of cool. Tell me more." Dean flicked open the top button on Sam's jeans and started to pull the zipper down slowly, tick by tick.
"Uh," Sam said, looking confused. "Well, another idea is, if a person who doesn't have their own kids to take care of ung." Dean had finished with his zipper and pulled Sam's half-hard dick out of his boxers.
"Go on."
"Um, if they help out with their nieces and nephews a lot insteeeahd..." Dean stroked Sam to full size.
"Yeah?"
"Then the person still passes on their genes, god, Dean, wha..?"
Dean traced a finger up the underside of Sam's erection, to the vein under the tip. Gently rubbing the spot, he said, "what were you saying?"
"It's called k-kin selection," Sam panted, and ran a hand through his hair.
"Hmm. What's that?" Dean slid his finger back down, stroked across Sam's balls, then gave a long pull up, ending with his thumb brushing over the tip.
"It's a, ahhuug, a whole big thing."
"You know, Sammy…" Dean squeezed, and pre-come obediently popped up.
God, Sam thought, why was Dean still talking? And expecting him to have an actual conversation? Confusion and pleasure swirled in his mind.
"I've noticed," Dean continued, "a 'negative correlation'" he caught Sam's eye and licked his hand wetly, eliciting a groan from his brother. Dean caressed the top of Sam's penis, collecting the pre-come gathered there, then slid his hand down the length. Sam closed his eyes and threw his head back hard, striking the car window and edge of the door but not seeming to notice. "Between the size of your cock" he pulled up and twisted "and the size of your words."
As Dean pumped up and down, he rolled his window down and a voice crackled through a speaker: "Welcome to Burgertime, can I take your order?"
"I'll have a bacon double cheeseburger, large fries, and chocolate shake. Sam, what're you getting?" Dean asked sweetly, and flicked his slit.
"AH, gaa, nugh!"
Crackle: "What was that? Please repeat your order."
"He said combo number nine."
Crackle: "Uh huh. Second window." Click.
"D-Dean…" Sam didn't have a follow-up to that. The fact that they were in the middle of a drive-thru had penetrated the fog in his brain, and he wanted to tell Dean to stop, but on the other hand, not.
Dean used his other hand to play with Sam's balls, gently juggling them with his fingers. He moved the Impala up in line, as the people at the window exchanged cash for a greasy white bag.
Feeling the car move, Sam gasped, "Dean!"
"Your vocabulary is suddenly really limited, Sammy, are you ok?" Dean pumped Sam's shaft with one hand, while he spiraled a finger around the tip, then rubbed the soft pad of his finger back and forth across the wet slit.
"Fuck - (gasp) - er!"
Dean started to pull the car forward again, and pulled on Sam hard, twist, down, pull.
"God, oh god, Dean!" Sam's come spurted all over his shirt, with a drop landing on his chin.
Dean stopped the car, leaned out the window, and grinned. "Darlin', I think we're gonna need some extra napkins with that."
~~<>~~
They ate lunch at a picnic table, watching the kids on the playground equipment and a jogger running in circles on the path around the small park.
"Dean, I can't believe you ordered me the fish sandwich combination."
"Hey, you ordered number nine. I believe your exact pronunciation was 'nugh.' Besides, you're a health nut and fish is healthy."
"Not deep fried reconstituted fish-bits slathered with tarter sauce!"
"I don't see you scraping off the tarter sauce."
"That's the good part. And it's not the point, Dean. I didn't say 'nugh' and it didn't mean nine."
"Oh yeah? What did it mean?" Dean waggled his eyebrows at Sam. "Was it part of your big evolutionary theory of gay sex? 'Cause you weren't making much sense at the end of that explanation." Dean's eyes sparkled with laughter.
Sam wanted to be irritated, but just grinned, because his brother was so goddamn gorgeous (how had he never noticed that before a couple of days ago?), and had just given him a hand job. In the middle of a drive-thru. Irritated after all, Sam said, "it's not my theory, and the point I'm trying to get at is much more specific anyway."
Dean slurped the last of his milkshake and licked his lips. As Sam's eyes followed Dean's tongue around those full lips, he suddenly felt a lot more charitable. "If you find us some privacy, I'll give you a demonstration." He held Dean's eyes and ran his tongue over his own lips, making his meaning clear.
They jumped up to clean the table and toss their trash, got to the car and, after a bit of impatient driving, found a wooded two-track. There had been a chain across it, but the thin latch had rusted through and the chain had fallen. The track curved, and ended in a clearing. Judging by the detritus on the ground, they weren't the first lucky couple to find this spot. They just had to hope a visit by a random patrol car wasn't as likely during the day as it would be on a Friday night.
Sam leaned across the seat and kissed Dean, long and slow and full of promise. When he got out of the car, Dean followed. Sam curved his arms around Dean's back, lowered them to his ass, and pulled their hips together. He traced the outer curve of Dean's ear with his tongue and whispered, "Get on the hood."
Dean's pupils were wide and his eyes already beginning to glaze as he complied. Sam pulled his own shirt over his head then took off Dean's. Sam's muscles rippled as he ran his hands over the only body he knew as well as his own. He stepped in for a kiss, and Dean spread his knees to let him come close. Sam's hands traveled down Dean's chest, paused to gently pinch his nipples to hardness, and continued over his stomach to the waistband of his jeans. His fingers dipped inside as Dean pressed his mouth to Sam's, thrusting his tongue in and out until Sam moaned.
Coming up for air, Dean gasped, "So what is this demonstration for? Not that I'm complaining so far."
"Shut up, I'll explain later." Sam unbuttoned Dean's jeans and lowered the zipper, thinking, this made twice in one day Dean wanted to talk during sex more than he did. He'd smirk if he weren't more interested in the light taste of salt on Dean's collarbone.
Sam tugged at Dean's jeans and boxers. Dean put his arms out behind him on the hood and leaned back, lifting his hips so Sam could pull the clothes down. After kissing his way down Dean's body, he took the head of Dean's cock in his mouth and sucked. Dean would deny the whimper that escaped him. Sam's tongue lazily circled the tip and he tasted pre-come for the first time. The newness of the taste, and of the experience, exploded in his mouth. He looked up to find Dean watching him with love as well as want in his eyes, and Sam felt his heart lurch.
Long licks left Dean's erection slick, and Sam slid his lips down, down. He consciously relaxed his gag reflex and took Dean nearly all the way in. Dean may have the gorgeous lips, but Sam had the large mouth in the family. He was too distracted experimenting with his tongue to imagine how Dean would reply if he heard Sam admit to having a big mouth, although judging by the sounds he was making now, Dean had no complaints. Sam managed to move up and down a few times with Dean deep inside his throat, before he had to pull up. He let his saliva run down, lubricating his hand as it took his mouth's place.
With a hand under Sam's chin, Dean pulled him up and into a kiss. He was surprised to hear himself murmur, "love you" against his brother's lips. He gasped as Sam twisted his hand around the head of his cock. When he felt Sam's breath tickle inside his ear with a whispered "I'm yours," Dean arched his back and came. Sam's arm was already around his back, lowering Dean to the warm hood as he panted, weak and spent. Sam's head rested in the hollow between his shoulder and neck for a while, then Sam disappeared to rustle around inside the car.
When he came up with some of the extra napkins from Burgertime, they both laughed.
~~<>~~
Sam was driving because Dean was too tired now, and he was talking because he apparently wanted to torture Dean.
"So, the point was, you went through all the stages of physiology and behavior without any feedback between the nerve bundles around your prostate and your conscious mind. The blood vessels in your penis dilated, your ejaculatory ducts opened, "
"What the hell are you talking about?" Dean felt free to interrupt because, for some reason, they were talking about his very personal anatomy.
"You got hard and you came."
"I noticed. Why the re-cap?"
"Because your body did everything physiologically necessary to impregnate a woman, "
"Were you and I at the same blow job?"
"without stimulation of the prostate."
"So?" Dean asked, then mentally kicked himself for encouraging the lecture.
"So, the reason anal sex feels so good, or at least one of the reasons, is because the prostate is stimulated through the rectal wall. The reason rubbing the prostate feels good is because it's surrounded by sensitive nerve bundles that send feedback to the brain."
"Ok, Sherlock, mystery solved, now shut up."
"But a lot of the body's physiological actions are coordinated by nerves and the subconscious brain, including, for example, dilation of blood vessels and opening and closing ducts."
"I hate you."
"You do not, you love me." Sam flushed and ducked his head, but went on. "The way nerves communicate with the brain is very precise, not just a random accident. So we have to figure out why a nerve pathway evolved that contributes to gay sex but isn't necessary for procreative sex."
They do? "We do not. Now shut your cakehole."
"I have a theory."
"Bunnies or midgets?"
"I just have to look at that research again when we stop for the night," Sam added, stepping harder on the accelerator.
Dean wished they hadn't gotten started on this in the first place. Mental pause. Except that it started because he'd fucked Sam and Sam had loved it. Small price to pay…
"Does this mean we get to experiment?"
Sam flashed him a grin. "You always were more into fieldwork than library research…"