Rainbow’s lungs burned, her body heaving as she struggled in vain to draw breath. She’d felt it before, when she was flying at the edge of space or fighting to tame a twister, but there was something about having her Mistress dishing it out that was infinitely better.

Her lungs worked, pumping themselves as wide as they could, but there was no reward for the effort. Her wings beat in instinctive futility, but the silk ropes tied around her legs kept her bound firmly to Rarity’s bed, the frantic effort to break free only serving to drive her muzzle more firmly against the unicorn’s slick folds. Rainbow drove her tongue deeply into her Mistress’ sopping marehood, eyes silently pleading as blackness began to edge its way into her vision, her own dripping loins burning as she came closer and closer to her climax.

Then Rarity would cum, again, and her magic would waver as Rainbow was washed with her Mistress’ sweet nectar. The magical bubble in Rainbow’s throat would flicker, letting a lungful of air past, and the weather pony would moan in a combination of relief and frustration as the entire process started again, sapphire-blue eyes and that gorgeous, white-furred face coming into sharp focus once again.

Rarity was watching her pet die between her thighs. It was a beautiful death, played out in the writhing of a pony pushed to the limits of equine endurance, the desperate need to cum matched against the equally desperate need to survive. Burning pleasure pitted against burning agony, each beyond anything that Rarity could inflict on her darling pegasus in any other way, each repetition lasting just a little bit longer, and carrying Rainbow that little bit closer to the point of no return.

But it was such an ugly death as well, played out in all the little ways that Rarity was forced to watch as she kept her beloved safe. Her sinfully skilled tongue slowly turned from a bright and healthy pink to more closely match its owner’s own hue, yet it never ceased to glide along the vibrant flesh that stood out from it in ever-starker contrast. Rarity whimpered as she felt another climax approaching, far too slowly for her tastes.

I won’t stop until I have to – and you know what that’s gonna take!

A bold promise, one that Rainbow would keep even if it killed her. One that, Rarity was privately terrified, was meant to do just that. Even with pegasus magic, there was only so much she could take!

Damn you, darling! Damn you and your sexy, sexy thrills!

She couldn’t deny that they were just that, either. Incredibly sexy, so much so that it hurt! As intimate as their lovemaking was, there was an undeniable primal thrill about holding Rainbow’s life in her hooves, as it were. That tongue, slowly growing less skilled, dragging out the time to Rarity’s next ‘excuse’ to give Rainbow some desperately needed air that little bit longer. The way Rainbow’s warm breath wasn’t washing over her between desperate licks, the way those gorgeous, magenta eyes slowly lidded and lost focus, glazing over as unconsciousness drew closer and closer.

But how to know when the line was reached? When the body had passed the point of “I’m going to turn off now, and we’ll have a long talk about how badly you screwed something up later,” and reached the point where le petit mort became… well… rather grand.

That brought to mind all too many very, very unsexy thoughts. Her beloved, forever still, limp and cold in her bed. Applejack, heartbroken, learning that a foolish bedroom game had cost her both of her loves. All of Ponyville, if not Equestria, mourning because she hadn’t been in control, when the very thing Rainbow had come to her for in the first place was somepony to take control. The very idea of having done all of that, merely because she couldn’t resist the those beautiful eyes plead with her, those beautiful, magenta eyes that were growing dimmer and dimmer every moment. Those eyes which slowly grew redder as lack of air and the alien pressures inside her throat caused the delicate blood vessels to flood to capacity, and then burst, pinpricks of scarlet staining the sclera.

Rainbow teetered on the brink of orgasm, her juices soaking the bed beneath her. She couldn’t make Rarity out at all now as anything more than a blur of flavors and sounds and the scent of sex. The blackness at the edge of her vision was just giving way to the faint sparkles that told her it was almost time….

“Polyester, darling!” Rarity cried out, scrambling back away from Rainbow as she ended the spell. Rainbow instinctively drew breath, unable to stop her body from sating its needs now that it could, but even as she collapsed to the bed, she was glaring at Rarity.

“What… the hay…? I was so close… that time!” She whined. “After everything I do for you and AJ, you can’t just give me one fantasy?”

“Rainbow, darling, I tried, truly I did!” Rarity protested, her ears flattening. “I am not going to kill you for the sake of an orgasm though, darling! Just look at yourself!” She floated a mirror over, showing Rainbow the scarlet stains that had finally scared her out of continuing.

“Bad ass!” Rainbow crooned. Then she noticed Rarity’s stricken expression, and flattened her own ears shamefully. “I uhm… I guess I really scared you, huh?”

Rarity nodded tearfully, undoing the knots around Dash’s legs and gratefully accepting the tender, warm, very much alive embrace that she was promptly offered.

“Sorry, Mistress,” Dash whispered. “Guess I forgot you get to freak out too, once in a while.”

“More often than most, I should hope,” Rarity teased, kissing Rainbow lightly. “After all, I do make something of a specialty out of it.”

“Yeah, you do,” Rainbow giggled, snuggling in close. “I’m sorry I scared you… but I can take it, y’know? I mean, I’ve flown in freakin’ tornados, for pony’s sake!”

“Yes, you have,” Rarity admitted. “But I’m going to need a bit longer before I’m truly comfortable with that sort of game. Maybe some research.”

“Oh, yeah, that’d be fun,” Rainbow snickered. “’Oh, Twilight darling, the next time you come back from Canterlot for a visit, would you be a dear and bring me a few books on how to strangle a pony half to death, but stop there?’ That wouldn’t be awkward at all!”

Rarity confined her response to the most deadpan glare she could possibly deliver. But after a few seconds of that, even she had to admit that Twilight’s reaction probably would be an amusing blend of excited to learn something new, and wary about just what such knowledge might be used for.

“I suppose I’ll just have to tell her it’s for when Sweetie Belle refuses to let me work,” she sighed dramatically. Both of them broke out into giggles, and enjoyed the mental images until they’d finally settled back into cuddling.

“Uhm… Mistress?” Rainbow asked sheepishly after a few more minutes. “I know you safeworded out and all, but… could you maybe finish me off?”

No response came from the unicorn, who seemed to be rather nonplussed at the request.

“Or at least give me permission to take care of business?”

“As I remember, you actually berated me for using my safeword, a very, very serious breach of trust. So just why should I give you an orgasm?”

Rainbow swallowed deeply, looking rather as though she wished the bed would just hurry up and swallow her already.

“I know, but I really, really need to cum….”

Rarity allowed herself a self-satisfied smirk before rolling on top of her pegasus pet.

“All right then, pet. I’m going to give you one that will take your breath away!”

Author's Note

Don't try this at home, fillies and gentlecolts! Remember, Rainbow Dash is a trained weather pegasus, used to operating in the much thinner air of the upper atmosphere, and even grew up in Cloudsdale. Between that and pegasus magic, she can handle going without air a lot longer than anypony else.

That, and she's a cartoon character. The fact that her eyeballs were able to penetrate a tree with no ill effects should demonstrate how minor a threat asphyxiation is. So if your eyeballs can penetrate thick trees as well, knock yourself out, but... well... we don't insure for that. :rainbowdetermined: