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In the Name of Science

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Sherlock almost went back to sleep. There was, he had calculated, a 2.137 per cent chance that something extraordinary would be happening today. Something, something not tedious. Something that was not water – salinity of 3.51 per cent, maybe 0.02 per cent more chloride than was usual, but not out of the ordinary range; there was the taste of…a school of lanternfish nearby (but he wasn’t hungry and could not be bothered and besides he didn’t want to look like Mycroft), no other predators, safety, boring boring BORING – something that was not seaweed or plankton or, well, lanternfish.

Or Mycroft.

That alone should have been enough to drive him into a deep slumber (fake one if necessary; his brother did not usually drift close to him in his search for food, so, yes, that perhaps was something out of the ordinary, and Sherlock could not believe he'd sunk so low as to be vaguely relieved that his brother was doing something slightly different.)

It was intolerable, unbearable, inconceivable almost, and-

Suddenly colder. Sunlight – what little reached down this far – blocked.

A few moments later, the ripples reached him. Sherlock turned. Above him, a bit to the left, one of those incredibly dull (not as dull as Mycroft) creatures that joined his world for a brief time every once in a while moved just underneath the surface of the water. He’d seen them before, moving in packs of two or three, sometimes more. He’d even brushed by a group once, but they did not understand what he communicated, thus did not reciprocate, thus became boring even more quickly than the plankton (which could be catalogued at least. So many varying shapes and tastes, but plankton never did anything interesting. Still, much more interesting than any of these four – four! Ridiculous! – limbed creatures.)

Sherlock considered swimming away, but there was Mycroft to think of – had to be planning something, might be interesting, but also infuriating, and Sherlock did not want to put up with Mycroft even if the alternative was … even if the only alternative was to acquire a specimen of one of these creatures – he really ought to give them a name – and see what not-so-boring reaction might be elicited from it.

Perhaps it was luck then that unlike most of its fellows, this one was alone. Brave – foolish – little thing.

John had only just noticed the – octopus? Squid? – out of the corner of his eye when it wrapped one long and surprisingly strong tentacle around John’s leg, and pulled. John froze, trying to figure out what, just what was happening – his mind blanked briefly. John was a trained soldier, however. He twisted, one hand going to the knife at his back – he never went diving without one, not since… no, not thinking about that. Definitely not thinking about…

…air running out because his foot caught. Mary beside him, sharing her air, until, until…

Another tentacle wrapped around him, his wrist; then another, his torso. John has plenty of air left, but suddenly it’s getting hard to breathe, and the knife does no good because he can’t reach, can’t hurt the creature.

There was a horror movie with just this plot, John was sure.

At some point – Sherlock had missed the exact instance; how irritating – it had extended a single claw. Interesting. The others hadn’t, but he had not come across as quite so threatening that time, he supposed. He would explain his purpose to this one, but it seemed unlikely it could understand him, and he hated explaining his actions to anyone in any case.

His reasons should be obvious.

Sherlock pulled the – it closer, reaching around with another arm to test the sharpness of the claw. There was a sharp pain. Quite sharp then, but no poison. And the fingers wrapped around – ah, of course. Not a claw at all, or not its own. It was using a tool; moderate intelligence then. Sherlock tightened his grip until the creature released its fake claw, a growling, gurgling sound emanating from the area of its head. He snatched the tool up in mid-sink. Later, he would try to see what kind of creature had donated the claw or if the – four limbs, tetrapod? Tetrapod! – if the tetrapod had actually made it. (Sherlock was leaning towards the latter.)

And the fingers. Different texture than the rest of the body, different colour, too. The grey might be a shell, not skin. No, no skin; definitely… Sherlock paused, mind going back to a previous encounter. He’d seen a few of the tetrapods without the grey-black covering, he was certain.

They were able to survive its removal then.

John cursed as the knife slipped from his fingers. Bubbles blowing out of the sides of his mask. The creature, squid, bloody monster snatched it, though, before it drifted away. Luck that. He'd get another chance at it if he could only free himself from the grip of the fucking Sea Monster of Doom, but it had most of its tentacles wrapped around his body by now, and the one that wasn’t was—John hesitated, angling his head in slow motion. No, no bloody way.

The squid was cutting open his diving suit; the edge of the knife was moving slowly. Trying to avoid cutting him, no, stupid. It was a squid, for god's sake. It was a squid holding him and cutting open his suit, sharp edge of the knife moving up his arm, to his throat.

John didn’t dare move; hell, didn’t dare so much as swallow as the knife closed in on his throat. The tip just barely not drawing blood from him, but the edge was there, the danger, and why was he so calm? Shock, one corner of his mind whispered. No, another answered. Not enough symptoms.

The knife stalled as it reached the upper edge of his suit, then with a quick flick, it cut through. The squid pulled at John's arm – removed the suit there. Another pause. Was it waiting for something? Was it confused? (Was he finally going insane?)

Sherlock waited for any sign of pain from the tetrapod, but there was none. In fact, it had become strangely docile, but Sherlock dared not lessen his grip. It might be a trick.

It might be paralysis.

No. There, a finger moved. Sherlock would continue. He quickly cut through the layer on the other arm, waited another moment – barely, but patience, patience. He was a scientist. He could be patient – then held the edge of the claw to the top and slowly drew it down the middle, cataloguing the reactions. The closer he came to the centre (no, not quite centre; a little lower), the stiffer the creature became. (Was it afraid for its vital organs? Where were its vital organs? Maybe he should cut it open entirely, once he’d catalogued all the reactions.)

No, not a vital organ, Sherlock thought as he pulled the skin away. A fifth limb!

The blade made its way downward, passing heart, lungs, liver, pancreas, intestines, oh god, and finally coming to rest just over John's cock. Don’t move, don’t move, don’t move! John didn’t know if he was directing this thought – going round, round in his head – at himself or the knife or the monster, but it didn’t matter because, fuck, fuck if it moved just a little downwards he would never fucking have children.

Never mind about fucking.

(Somewhere at the back of his mind, John noticed that he was conserving air by not breathing, and that while conserving air down here – Mary, oh Mary – was good, he needed to breathe or he might pass out. Passing out was bad. It was a good thing, too, that his air tank was trapped between his body and the monster because John wasn’t sure for how long the squid would leave the straps of the tank alone. He very firmly avoided thinking about what he’d do if the thing removed his mask.)

The tentacles undulated then, pulling off his diving suit until the tattered remains were floating around John’s feet and he was bared to the – sea world and to eyes the size of plates. Creepy. Creepy and horrifying, and John whimpered as a tentacle floated towards his member because he could feel the suckers on his chest, feel their sharp, painful edges as they attached themselves more fully – thousands of them –, and he didn’t want them anywhere near his most delicate body part.

Jesus. Jesus Christ.

A pentapod then. Incredible. He’d have missed this if he hadn’t removed the outer skin. Sherlock hesitated over the limb. It looked like a stump compared to the other limbs. Mutilation? (No, no visible scars.) Slow growth? He needed more data. Sherlock careful trailed a finger along the stump. He’d barely even touched it, when the creature stiffened impossibly further. Curious. He repeated the motion, and the pentapod emitted a gurgling sound. No further stiffening, however. Both reactions hinted at the possibility that the stump was sore. Of course, it was incredibly hard to tell with these creatures.

And the stump was simply so very interesting.

Sherlock poked at the tip, pulling a little and discovering to his delight that there was a small amount of extra skin. He rubbed back and forth, noting that the creature began to shudder within his grip. Annoyed, Sherlock tightened his hold, moving his arms around and wrapping them more securely around the pentapod.

Then he went back to the tip.

John let his eyes snap shut as the tentacle monster returned to rubbing at the glans of his cock. The tip of its tentacle was slick, no suckers there, and the friction and constant motion (up, down, around, up) had him swelling slowly, but surely. It was maddening, and frightening, and yes, exciting, and oh god, but John hadn't felt this alive since before returning from Afghanistan. His heart beat at the pace of a machine gun, and white trails of lights were dancing on the inside of his eyelids, and his brain kept telling him, "yes, yes, this" (this is why you were diving alone; not because you couldn't find anyone but Mike and one of you needed to stay in the boat; no, it's because you'd hoped that something, anything, would happen. Something exciting, and new, and above all dangerous.

John, it said, you're an adrenaline junkie of the worst sort.).

The sort, in fact, who'd get himself killed. Unless Mike would come and check on him. He would, when time would start to run out, but would he be fast enough? Would he be able to do anything to get that tentacled monster off of John?

John didn't know, but the thought of dying here aroused him even more.

Sherlock paused, momentarily bemused, as a substance began to leak from the limb. He let his finger drift over it, tasting. Salty. Perhaps, ah, of course. This limb was a hectocotylus, which - if it worked in any way like that of his own species - would explain the small size. One didn't regrow such an arm in a day after all.

Of another kind of interest was the fact that it was leaking sperm, which would indicate a willingness to mate with Sherlock, which was...a little strange. This was a species that could not communicate with higher life forms, yet clearly possessed some intelligence, and yet, also clearly, could not procreate with his own, at least not with Sherlock, who also happened to be male.

Unless, of course, these creatures changed their sex upon need as clownfish did. Or maybe they were like sea horses where the males carried the young. Perhaps...perhaps they were able to do so as well. It was worth testing surely.

Sherlock let his own hectocotylus wrap around the pentapod's body, searching for an orifice. Not the mouth, he thought. They breathed that way and it wouldn't be very logical to obstruct the airways during intercourse. (Then again, some species were downright illogical about some things.)

Ah, here. Behind the hectocotylus (to avoid self-insemination? The arm was rather stiff.). Sherlock carefully pushed the tip of his own arm inside the opening, waiting to see what kind of reaction this would garner.

The creature blew out more air and gurgled again. Its hectocotylus began leaking harder.

Sherlock took this as encouragement to continue.

If the situation hadn't been incredibly surreal before, it certainly was now. John gasped as a tentacle (another one, how many fucking were there?) pushed at the entrance of his anus, breaching it, then stopped. An eternity passed in a moment as John waited, unable to really grasp the sudden intrusion. What he was waiting for - what he wanted - he couldn't really say. For it to stop? (Normal. Normal people would want that.) For it to continue, maybe pushing all the way inside in one fell swoop, not caring (an animal, it's an animal) whether it hurt John or not. (He should not want this, should not get more aroused at the thought, but he was, Jesus, he was.) For something else entirely?

What he got was best described as a slow exploration, the creeping of a single tentacle, the light brush now and then against his prostate as the tentacle began to - not draw out, no - to undulate inside him. It wasn't growing, it wasn't. But more and more of it found its way in, writing, now almost constantly pressing and rubbing against his prostate, leaving John close, so close on the edge of orgasm as he gasped and gasped and gasped, and finally noticed that the air tank must be nearing empty (how much time? How much? Where was Mike?).

Then a burn started inside his hole, spreading, leaving him writhing with the last of his energy and the last of his oxygen, and John realised he was going to die; he was going to die because the tank was empty; and the black spots before his eyes - wide open now, wide open and staring at the monster - multiplied as with an explosion he came.

And then there was darkness.

The pentapod let his seed spill into the ocean (wasteful) shortly after Sherlock had deposited his own inside its body. Following that it went entirely limp in his arms (exhaustion? yes, must be), so far, not an entirely surprising course of events. However, the sudden decline, then lack of bubbles rising up from its mouth was rather worrying. Either these creatures died after intercourse (doubtful) or ... it had run out of air like whales did. (Logically, it really lived more on the surface of the ocean.)

Sherlock pushed upwards, dragging the limb body of the pentapod with him towards one of the long plank of wood that these creatures took their dives from. There, splashing in the water, was another of the creatures. Surely it would know what to do with its companion? Sherlock hoped.

He hoped that his pentapod would survive, and that it would return. After all, there was a chance of cephalopod-pentapod offspring.

And Sherlock wanted to observe it.