Rating: NC-17, for vaguely described violence, death, and... well, sex.
Spoilers: "Sleeper" and Owen's report on the Himalayas (taken from the BBC website).
Summary: It's become something of a running joke.
The first time Owen says it, they're both drunk.
Jack has been gone a week, and Ianto is trying desperately to keep the team from crumbling. He's finally coaxed Gwen into going home to Rhys, dragged Tosh away from her computer and onto the sofa for a nap, but Owen is stubbornly refusing any sort of care or comfort. So Ianto pulls a bottle of whisky from Jack's private stash, and he and Owen sit on the floor by Jack's desk, passing the bottle back and forth, not really speaking.
Ianto isn't exactly sure what this is going to help, but he has to do something, and this is the only thing he can think of.
"Do you know what we should do, Ianto?" Owen says, and he's far past drunk now, so far gone that Ianto can't think of a word to describe it. "We should all have sex. You, me, Tosh, Gwen... Let's all have sex. Sometime."
It's such a non sequitur that Ianto is stunned into silence. Finally, he sighs and says, "Owen, you're drunk."
"That doesn't make it a bad idea, though," Owen says.
Ianto doesn't say anything more, and after a while, Owen passes out on his shoulder. The bottle is empty, and Ianto carefully sets it aside. He tries to get comfortable, but his head is awkwardly bent, the wood of the desk is hard behind his back, and Owen's elbow is digging into his ribcage. Then Owen starts to snore. Ianto sighs and resigns himself to another sleepless night.
The second time Owen says it, Ianto is still shaking, because they should be dead now. They should all be dead, but they're not, and he knows he should be glad, and maybe he is, but he can't stop shaking.
Owen drops his weapon and stares around at the carnage, blood and flesh and ichor and all sorts of things everywhere. "I don't fucking believe it," he says. "We're not dead."
"No," Ianto agrees. It seems like the sensible thing to do. "We're not dead."
"Let's all have sex," Owen says, in a bemused sort of way, like he doesn't mean it, but doesn't know what else to say.
It sets Gwen off, though, and she flies at him, her fingers curled like claws. He catches her wrists, holds her a safe distance away as she swears at him. "You bastard! After all that, and all you can say is--" She breaks off with a sob.
For a moment, they all stand there, Gwen and Owen locked together, Ianto and Tosh hovering uncertainly nearby. Then Gwen crumbles, but Owen catches her, wrapping his arms around her and letting her sob into his shoulder. "If you hadn't..." Her words are shaky, broken by her choked breaths, muffled by Owen's shoulder. "And Tosh and Ianto, they could've been... I can't do this, Owen. I just can't."
"It's all right," Owen says, stroking her hair. "You did fine, Gwen. You did just fine."
Ianto feels Tosh's hand slip into his. He stares down at her, and the relief finally starts to hit him. They're not dead. They're still alive. They killed the monster and they saved the planet and they did it without Jack.
Maybe next time, things will be worse for them, but right now, they're still alive, and that's what counts, in the end.
The third time Owen says it, he's already got his hand up Tosh's skirt, and by the little, ragged whimpers coming from her throat, he's quite good at that. "Let's all have sex," he grunts, as her leg wraps around his waist and she licks his neck and his fingers work busily away.
Ordinarily, Ianto would say something now, something about pheromones or biological agents and why they really, really shouldn't be doing this. At the very least, he'd like to point out that Actually, Owen, we are all having sex. But his mouth is full of Gwen's tongue, and it's sloppy and it lacks finesse and it's probably the greatest thing he's ever felt in his life, and then she's backing him up against the wall with a low growl like a jungle cat, and he forgets all about everything and starts ripping off buttons in his haste to get into her shirt.
Then they're on the floor, all of them in a pile, and it's hands and lips and thighs and breasts and buttocks, dark flowing hair, the sharpness of Owen's hipbones and the feel of Tosh wrapping herself around him, Gwen's head thrown back and the line of her throat exposed. It's damp heat and friction and the most pornographic noises Ianto has ever heard (or made) in his whole life. It's probably the most ridiculous, idiotic, nonsensical thing that has ever happened to them, and it is, without a doubt, the best sexual experience he's ever had in his life.
And the others seem to agree, because when he suggests slipping a little RetCon into their coffee the next morning, they quickly decide that it isn't necessary. They're all blushing and covering themselves with whatever scraps of fabric they can find; they're all covered with bruises and bitemarks, but no one wants to forget what they've done. And though he'll never look at any of them the same way again (Tosh in particular was a surprise), Ianto is secretly relieved by that.
(The fourth time would have happened while they were snowbound halfway up K2, with their helicopter and half their supplies wiped out in an avalanche. They would have all been crowded into one tent, clinging to each other under two sleeping bags zipped together. Ianto would have had one hand pressed to Tosh's chest, feeling it rise and fall with each of her shallow, uneven breaths. His head would have throbbed; his thoughts would have been increasingly vague and scattered; his limbs would have felt heavy and unwieldy. He would have remembered that for every two climbers to summit K2, one dies. He would have found himself listing the names off in his head: Nick Estcourt, died in an avalanche. Art Gilkey, thrombophlebitis. Alison Hargreaves, caught in a storm on the descent. Jeff Lakes, exposure... He would have thought of all the great climbers who had died, and how his team were not great climbers, and how their odds of survival were decidedly poor under the circumstances.
Then Owen would have spoken up from the other side of the pile, in a voice that sounded like he was drowning in broken glass and his own blood. He would have coughed, and said, "As long as we're all cuddled up like this, let's all have sex." And then he would have coughed again, and Gwen would have been too silent, far too silent, and Tosh would have stirred under Ianto's hand, but not regained consciousness. Ianto would have had to squeeze his eyes tight shut, then, to hold back the tears.
It would have been the last thing Owen ever said.
But it never happened.)
By the fifth time, it's become something of a running joke.
Jack is back, although no one's really forgiven him for leaving yet, and they're all deferring to Gwen's judgement a great deal more than Jack seems to think they should. There are alien sleeper agents planted all over the world (or Cardiff, at least), and nuclear weapons, and although Jack and Gwen have headed off to avert the crisis (and they probably will), it could still be the end of the world.
Ianto, Tosh, and Owen are gathered around Tosh's computer, watching it all happen, when Ianto takes a deep breath, and says significantly "It's the end... of everything."
And Owen, with just as much seriousness, replies "Let's all have sex."
And somehow, Ianto knows that everything is going to be all right.