Planning for “Unexpected” Rainshowers
A story about Ayda Moon, 19-year-old hermaphroditic wolf, and Olivia Moon, hir 13-year-old sister.
It had seemed like such a good idea at the time. Ayda was living on hir own, a university student freshly finished with hir first year, in an adorable two-bedroom cottage just beyond the edge of the college town but still within comfortable walking distance of everything. It just made sense for hir to invite hir beloved little sister to stay with hir for the summer. They'd miss each other too much otherwise, and their mother could use a break.
But weeks of close proximity, of late-night chats and cuddle sessions and unintentionally sexy antics had stoked the fires of Ayda's lust into a blaze. Shi was losing hir mind, drooling over hir own thirteen-year-old sister and popping inopportune boners like a middle-schooler. Shi was masturbating hirself unconscious every night just to get by, but it wasn't enough. Something had to give.
So Ayda planned.
And on a bright, beautiful, cloudless day early in summer when the heat hasn't quite gotten unbearable, Ayda Moon invites hir little sister, Olivia, on a picnic.
Ayda thinks shi does an admirable job of not checking Olivia out too obviously as she sits so cute on the gingham blanket. Her fur looks so gorgeous—silky smooth and shiny; ashy grey over most of her body, with white socks and gloves that end right above her ankles and wrists. And her belly fur. It's white, too, running from her chin, down her throat to where it disappears underneath her sundress. Ayda wonders how far it goes. From earlier peeks at her midriff when she has stretched and her shirt has run up, Ayda knows it's at least below her waist. Does it go all the way down, like Ayda's? Are her inner thighs white, too? The idea of running hir hands through Livie's pubic fur flashes through hir mind, and shi pants. Shi shifts hir legs to hopefully hide the growing evidence of hir arousal and turns hir eyes and mind elsewhere.
"It is a little hot, isn't it?" Olivia remarks, muzzle upturned and eyes closed, billowing her sundress by its collar. It's cute; a cute dress for a cute wolf—white, printed with pink and yellow lilies. Ayda hirself is wearing an airy blouse, unbuttoned at the top to show off hir fluffy cleavage, and cotton capris, loose enough to not emphasize hir package without being so loose it can be missed. Shi's proud of hir hermaphroditic gift, shi has no need to hide it.
"But," Olivia continues her thought, drawing Ayda's attention back to her smile, "I like it. The sun in my fur feels nice. Like a hug." She flops backwards to starfish out on the blanket, and Ayda's question is answered by her dress fluttering up from the motion—
Livie's inner thighs are white.
Shi doesn't get a clear look at Olivia's panties, but feeling guilty and self-conscious and all-too-aware of the warmth pooling inside hir and soaking hir own panties to hir pussy, Ayda scoots over to sit next to hir sister. Olivia sighs, contented. Ayda smiles.
"Full belly and sun in your fur, you fallin' asleep on me, Liv?" Shi reaches out to pat Olivia's belly affectionately. 
Olivia hums and nods, lifting her hand to lay it over her older sister's.
"Okay. You enjoy your nap. I'll wake you up in a bit."
The younger wolf doesn't even answer, already drifting off. Ayda turns hir attention skyward, to find clouds on the horizon, right on time.

Olivia is still snoring gently when the clouds open up in a downpour. She shrieks awake, flailing up in a way that has Ayda giggling. There's no way for either of them to avoid being soaked to the bone near-instantly, but Ayda makes a show of hurrying their picnic into hir arms and rushing off to the backdoor with hur little sister anyways.
As they stand dripping under the awning, Ayda gives hirself a moment to take a deep breath and give hir little sister another once-over. Olivia isn't wearing a bra. Shi had hir suspicions from the way it sat on her shoulders, but it's painfully obvious now how her little nipples, hardened by the cold and the wet, show through the soaked white fabric. 
Ayda makes a show of shaking out some of the water from hir coat while shaking lewd thoughts from hir brain.
"Okay! Here's the plan!" Shi has to yell for Olivia to hear hir over the din of rain on the awning. "We get in, you go straight for the bathtub! Strip down and get a nice, hot shower to warm back up so you don't get sick! I'll dry off real quick, then run and get you something to wear! Okay?"
Olivia nods, already shivering.
Ayda throws open the door and they rush in, claws clacking on the floor. Shi tosses the basket into the sink then follows Olivia into the bathroom right as the younger wolf closes the curtain. Shi drops the sopping wet blanket into the washer, grabs an old beach towel, and pats dry enough of hirself to not make too much of a mess on the floors and carpets. Then shi looks up.
Shi hadn't really ever considered how fucking transparent hir bathroom curtain is before right now. Shi can't make out any details, but shi can see the broad strokes of hir little sister struggling out of her sundress. Shi tears hir eyes away, strips down to hir panties, adds hir bra and outerwear to the washer, and hurries from the bathroom.
What Ayda has always officially called the "guest bedroom" is really just the place shi put all the various accumulated junk that shi didn't have another place for. But this summer, it's Olivia's bedroom. Not that shi could tell, since Liv spent so many nights in bed with her big sister. Shi pauses in front of the full-body mirror to check hirself out and hir eyes snap to the reflection of the tip of hir cock poking out of hir sheath and just showing over the top of hir panties. Shi points down at it threateningly.
"You listen here, I did not spend the last month dying out there, and the last two weeks meticulously planning this for you to screw it up by jumping the gun. You need to calm the fuck down, or we won't get to fuck. down. Whatever! No boners 'til she's comfortable with you, okay? Okay." Shi nods for emphasis.
Shi opens hir sister's upper-left drawer to find her underwear. It's all folded and carefully arranged and darling. Shi considers hir options thoroughly. If the plan works, shi may not even need them anyways, but shi settles on ice-blue bikini panties, to match hir sister's eyes, because apparently shi's a sap. Shi allows hirself a grin, proud of hir carefully-chosen words at the backdoor—something to wear, singular. Clutching the panties carefully in hir clawtips to avoid dampening them with any of hir still-wet fur, shi shuffles back to the bathroom.
As shi stows the panties on the shelf with the spare towels, shi calls out, "got your stuff! Where's your wet clothes?" Before shi gets an answer, shi approaches the tub and grabs them from across the curtain rod. "Found 'em! You warm enough in there?"
"Mmmmmhm!" comes Olivia's reply from the cloud of steam.
[[“Talk about sudden rainshowers, huh?”]]
As Ayda places hir little sister's sundress and panties—BLACK AND LACY??? FUCK—into the washer, shi calls out, "Oooh, no bra today? Daring, baby sis!"
"Ayyyyyydaaaaaaaaaaa," Olivia whines back.
Giggling, Ayda loads a few of hir best towels into the dryer and starts it up. Hot, fluffy towels for when they finish!
Shi peels hir panties down, grimacing at how they cling to hir cunt, tosses them into the washer with the rest, and approaches the shower.
Playing up hir shivers, Ayda pulls the shower curtain aside just enough to slip through. "Brrrr! Scooch over, lemme warm up too."
Olivia is frozen, hands raised still lathering her thicker headfur, eyes wide. Ayda acts casual.
"Oh, that's nice and warm!" Shi pretends not to notice how hir little sister's eyes drift down from hir face, flicker between hir breasts—yes, they are excellent, nice round tits with an excellent balance of heft and perk—then settle on hir sheath and scrotum—yes, they are excellent, a plump sheath and big balls so full of cum—before jumping back to hir face. Ayda focuses on not getting an erection while shi starts hir own shampoo lathering and waits for Olivia's attention to shift. When it does, shi takes in hir little sister's body.
She's so fucking cute. No wonder she wasn't wearing a bra, her boobs are tiny. They're perfect little things, just the slightest hint of curve, with perky little nipples to match. And her pussy! Her sweet little cookie parked right between her slender thighs, puffy and oh-so-delicate. She's beautiful, gorgeous, slim but with a tomboyish charm of muscle tone. Fuck, Ayda needs her.
"Sis?" Olivia is looking at hir, did she notice hir staring?
"Huh?"
"I—" Olivia hesitates, seems to chew on her thought, "I asked if you're really a herm?" She looks pointedly at Ayda's crotch as she asks.
"Oh!" This is maybe too perfect. If Ayda hadn't just been staring lust-brained at hir little sister's pussy, shi'd probably be worried. But shi was just staring lust-brained at hir little sister's pussy, so shi isn't worried. Instead, "Yeah, here." 
Shi turns to fully face Olivia, cocks hir hips forward and spreads hir legs a bit. Shi scrubs at hir headfur and focuses intently on not thinking about the erection shi is currently shoving in hir sister's face. 
"Lift my balls out the way."
And Olivia does it. She leans down a bit and uses her hand—small, delicate, perfect like the rest of her—to cup and lift Ayda's balls and look at hir spade. 
In hir mind, Ayda chants the mantra do not cum on your little sister's face, do not cum on your little sister's face, do not cum on your little sister's face.
"See? Pussy, just like you." Shi congratulates hirself on how very normal and not at all horny hir voice sounds.
"Huh! Neat." Olivia leans back away, goes back to cleaning. "Yours is prettier than mine."
And well fuck! What is Ayda supposed to say to that! Hir mouth goes dry. Shi clears hir throat.
"Really? I dunno, lemme get a look at yours." Shi crouches down.
Olivia presents her pussy for her big sister's scrutiny. Just really shoves her whole pussy right at Ayda's muzzle. Ayda thinks shi may die. This is going so much better than shi had expected.
Ayda observes Olivia's pussy. Shi scrutinizes that pussy. Shi commits that pussy to hir memory, burns the image of that pussy into hir brain to keep forever, just in case. It takes a monumental effort not to shove hir snout into it and eat hir little sister out right here. Instead, shi hums approvingly.
"Maybe we'll just agree to disagree," Ayda offers, "because that is the prettiest pussy I've ever seen.” Shi stands, not really thinking about how close shi still is to Olivia, or the rampantly hard erection shi has, until hir dick brushes up hir little sister's thigh and across her pussy on its way by. "Oops," is hir extremely eloquent response to rubbing hir throbbingly erect cock against hir little sister's bare spade.
"Oh wow."
Olivia is now staring at Ayda's cock as it throbs.
"Did that happen because of me?" she asks, all bashful.
"Uh, yeah." Pull it together, Ayda.
"Wooowwww." There is wonder in Olivia's voice, in the way she draws out the word, reverent. “It's so big. I guess you weren't lying about liking mine more, then, huh?”
Ayda no longer thinks shi may die, shi is certain of it.
“Hard to lie about things like that with one of these,” Ayda offers, then adds, “but I wouldn't ever want to lie to you, about that or anything else.” Shi puts on hir best loving big sister smile.
The blush and grin shi gets from Octavia is worth more than anything else in the world.
“Now, how about I help you scrub down before we run out of hot water?”
Octavia looks like she was about to say something else, but seems to slip readily in this new direction, as she smiles and nods.
A few minutes—and a few wandering hands—later, both are clean and ready to get out. As shi twists the water off, Ayda declares, excitement in hir voice, “I have a surprise for you! Hold still here.”
Then shi hops out of the shower, scurries across the room, and opens the dryer to retrieve two of the warm towels. One shi drops onto hir own head. The other shi holds open and wraps up hir little sister, capturing her in a warm, fluffy hug.
“Let's get you nice and dry now,” shi says as shi nuzzles into the top of Olivia's head.
After a moment of “helping” that mostly just involved tickling Liv with the towel, Ayda switches off to drying hirself. Shi notes, thankful, that the sudden chill of stepping out of the shower coaxed hir cock back into its sheath for the first time since shi had entered it.
When that business is done, shi hangs both towels on the rack, then grabs one more from the dryer.
“And now, my secret weapon!” 
With a flourish, shi wraps up hir little sister in the towel and scoops her up, sending her into a fit of giggles. Pausing just long enough to grab those panties from the shelf, shi carries Olivia all the way to hir own room, throws back hir bedcovers, then tosses the girl onto the bed still burritoed in the towel.
“Now, baby sister, you have an important decision to make,” shi declares with all the seriousness shi can muster. “Do we cuddle with you wrapped up and me outside the towel, or do we unwrap you and get us both under it to cuddle?”
Olivia is fighting her way out of her bindings before Ayda even finishes.
With arms reaching out, Olivia remarks, “We've never cuddled naked before, I wanna know how good it feels to have all your fur against mine.”
That's all the convincing Ayda needs. Shi drops the panties on the bedside table and climbs in with the girl. It takes a moment of negotiating angles before they're on their sides facing one another, Olivia's muzzle tucked between Ayda's breasts, with the still-hot towel on top of them, then the duvet over that to trap the heat. Ayda runs hir hand slowly up and down hir little sister's back, claws leaving trails in her fur, and places a kiss atop her head.
“I love you, big sis.”
Ayda feels Olivia kiss hir breastbone.
“I love you too, little sis.”
Shi squeezes hir sister just a little tighter.
“Is that your, um, penis, again?” 
Oh, right, Ayda is horny.
“Yeah.”
“Can I touch it?”
“Yeah.”
Olivia slides herself back and down, enough to free her muzzle from its boobytrap and get a good look down. Ayda can feel her breath on hir cock.
Then Ayda can feel her pawpads on hir cock, gently, tentatively exploring. Then Olivia's hand closes around it—not quite making its full circumference—and begins stroking. Ayda lifts the blanket and towel enough to watch.
Shi is caught by surprise when shi watches—and feels—hir little sister lick the bead of precum from hir cocktip. Shi moans.
“Did you like that, big sis? When I licked you?” Olivia is looking up at hir now, beautiful crystal-blue eyes locked in on hir. 
“Fuck, so much. I loved it, babygirl.”
Olivia grins.
“Good.”
Olivia takes her big sisters cock into her muzzle.
Ayda would, under most circumstances, consider hirself a capable and long-lasting sexual partner. But when hir little sister, whom shi has been lusting after for the better part of a month (not counting the probable years before shi moved out), begins sucking hir off, hir balls clench up and shi fires immediately.
“Oh shit I'm c-cumming,” shi stutters out, just in time for the first jet of hir semen to pulse from hir cock and into Olivia's maw. 
Olivia does her best, but can't keep up with her sister's production, and ends up pulling away with a gasp as shot after shot of cum splatters into the fur of her chest.
When Ayda's mind and body reunite, shi finds hir little sister, hir darling, precious, beautiful little sister, sitting up watching hir. She looks so proud. She's practically preening. 
“Liv, oh Livie.” Shi takes a moment to catch hir breath. “That was such a good job.” Then shi notices the cummy mess shi made of Olivia's chest. “Oh baby look what I've done to you, all in your clean fur.” Shi gets an idea to reciprocate. “Come here, let me get that for you.”
Olivia crawls up along her big sister's body until Ayda can grab her, pull her in, caress her, press another kiss to the top of her head. Shi pauses. Then shi kisses hir little sister's lips. 
It's short, too short, and both are left wanting more, but Ayda has a mess to clean up. Shi lifts hir sister further up, then sets about licking hir own cum out of Olivia's fur. The smell of both their arousal fills the air, and Olivia is panting by the time Ayda finishes, but then shi begins laving at her pert little nipples with hir broad tongue. Olivia's breath hitches, and Ayda sucks down on her left, pulling away with a pop.
“Let me return the favor, Livie?”
Olivia nods, face flushed as she pants. Ayda lays her out on her back, kissing and licking a trail along her body from her muzzle, down her throat along the edge of where her fur changes color, stopping to give each nipple more attention before continuing down her trim belly to that perfect spade pussy clenched between slim thighs.
Ayda eases hir little sister's legs apart. Already shi can feel hir dick pushing its way back out of hir sheath as shi beholds once again the most beautiful pussy shi's ever seen. Shi lays a hand over it, reverently. As shi cards hir fingers through the dense white fur there, shi looks up to make eye contact with hir little sister, who shi finds is watching hir with hands clutching the bedsheet.
Without looking away, Ayda reaches hir free hand up to take one of Olivia's and lace their fingers together.
“You are so beautiful, baby sister.” Shi places a single, loving, gentle kiss to the spade before hir. “I love you.”
“I love you too.”
Then Ayda mashes hir whole muzzle into Olivia's waiting pussy. The taste, the smell, the feel of it are all intoxicating, driving hir mad. Shi licks, and kisses, and nuzzles into it with fervor, rapidly driving Olivia over the edge.
Olivia keens as she tenses up, lifts her hips up from the bed to press harder into her big sister, clutches hir hand. All the while, Ayda continues hir ministrations. When Olivia drops back down, shi stops with one last sweet kiss to her clit.
Sliding back up the bed, Ayda gathers hir little sister in hir arms, cooing endearments and affirmations. With Olivia pressed against hir, shi rolls onto hir back, so Olivia lays atop hir, head pillowed on a breast. Shi returns to petting up and down hir sister's back, other hand splayed across her butt.
Olivia lays there, boneless and blissed out, for several minutes. Her first motion is to rock her hips against the erection pressed between their bellies. Her tail wags.
“Welcome back, babygirl, how was your trip to space?” Ayda keeps hir voice low and soft.
Olivia moans into the side of hir boob.
“Oh my god, big sis.”
That gets Ayda to chuckle.
“Was it that good?”
“Yes. It's never felt that good before.”
Ayda grins, proud of hir accomplishment.
“I still can't really feel anything. I'm all numb and tingly.” Olivia gives another shiver as aftershocks roll through her body.
“Well you lay there as long as you need, baby. Big sis has got you.”
Olivia nuzzles deeper into Ayda's boob, gives a couple—unintentional?—humps at the still-erect cock she's straddling, then goes still. A moment later, she's snoring softly. Confident that between the shower, the towel, and the orgasms, they're both dry and warm enough, Ayda doesn't try to fix the covers where they've fallen away from the two of them.

When Ayda awakens, shi comes to realize several important facts.
One: Shi and hir sister are still nude, still cuddling.
Two: Hir cock went flaccid and retreated into its sheath sometime while shi was asleep.
Three: Its tip is now peeking back out.
Four: Hir little sister is perfectly positioned so that her pussy is kissing Ayda's sheath.
Five: As it stiffens, hir cock has nowhere to go but into Olivia's vagina.
Fuck.
Shi wants this. Shi needs this. Olivia is still asleep, shi could feign sleep hirself for plausible deniability. And maybe if shi were still asleep too, it would be fine. But shi isn't, shi knows shi's penetrating hir unconscious little sister, and somehow this is a line too far.
Ayda tries shifting hir hips, just a bit, to free hir cock, but then Olivia's hands clutch at hir.
“Please don't move.” Olivia's voice is desperate, thick with need. Ayda freezes. “Please. I want to feel it get hard in me.” So maybe she wasn't asleep after all.
Ayda hesitates.
“Are you sure?”
Olivia nods into hir tits. “I'm sure. Please.”
Ayda settles back down, wraps hir arms around hir little sister, and lets it happen.
“Oh, wow.” Olivia's pussy clenches around Ayda's tip. She keeps repeating those words, “Oh, wow. Oh, wow. Oh, wow.” Every time a little breathier, a little more like a moan, as her virgin vagina is spread further and further by the cock penetrating her deeper and deeper. And then it's fully erect, and Olivia sighs out her pleasure.
She's so damn tight.
“Don't back out now.” Olivia sits up, flexing the cock inside her, to look down at her big sister with her hands fisted on her hips. It is far more adorable—she's so small, so cute, so perky and slim and sleek and and—and far more sexy—she is fucking naked and Ayda's fucking cock is inside her fucking cunt—than whatever she's trying for. “I have been waiting for this for so long..”
That gives Ayda pause.
“You have?”
Olivia throws her hands up, “Yes!” She scritches at her own head, tugs at her own ears. “I have wanted you since before I even knew what wanting you means. And then you moved out and I thought 'oh it's over' and then you invited me out here to live with you and I thought 'this is it'! And then nothing! I tried playing it subtle, stick out my butt and lift my tail as you pass, 'accidentally,'” she makes air quotes with her fingers while rolling her eyes, “forget to wear a bra under a loose-fitting top, press my butt into you when we cuddle, and all you'd do is stare and be awkward about your hardon that I wanted you to have!” She's on a roll, and doesn't let Ayda get a word in as she keeps on. Ayda probably couldn't speak even if shi wanted to, though. This is kind of a big revelation for hir. Olivia wants this, too, and all the sexy antics shi thought were accidental were very much intended.
“And I thought to myself 'if I have to listen to hir noisily fuck hirself to sleep one more night, I am going to strip down and barge in there with my fingers in myself and beg hir to breed me'!” She sighs, then continues in a calmer voice. “But then I found your notes.”
Ayda's eyes go wide and shi finally finds hir voice.
“What notes?”
“Your big secret plan.” That causes Ayda to panic briefly. “And it was sweet. A little manipulative, doing all this just to get between my legs, but sweet.” She affectionately pats Ayda's right tit and rubs hir belly, soothing away hir worry. “So I waited, and I played along, and now I finally have you inside of me and please, please don't make me get off.”
Ayda slides hir hands up hir little sister's thighs to hold her by her hips. Then, as the words turn over in hir head, shi catches a perfect opportunity and grins. Shi holds tighter.
“Oh, I'll make you get off alright.” Shi grinds hir hips up into hir little sister and Olivia moans up at the ceiling as a shiver runs through her body. 
When Olivia looks back down, her face is equal parts love and exasperation. Ayda just grins all the wider.
“So, can we do this?” Olivia asks.
“Do what?” Ayda knows exactly what Olivia means, but wants to hear her say it.
“Please, big sis. Make love to me.”
And oh, her word choice. “make love”. Not “fuck me”. Not “breed me”. “Make love to me”.
“I love you, Livie.” Ayda reaches one hand up from her hip, tracing along her side up past her nipple to cup the side of her face. “I love you so much. Yes. Yes, let's make love. You wanna stay on top?”
“Please, at least at first.”
“Okay, baby. You lead.” Shi drops hir hand back down to Olivia's hip.
Olivia moves her hands up to grope her sister's breasts as she starts moving her hips with slow, measured grinds.
“I love your boobs.” She gives them both a gentle squeeze. “They're so big, so soft.” She runs the pad of a thumb in a little circle along the edge of Ayda's areola. “I love your nipples, the way your fur lays around them. I wanna play with your boobs.”
“Well now you can, Liv, any time you want.” Ayda moves a hand up to settle it over one of Olivia's. “I'm yours, you're mine, my boobs are yours to play with, baby.”
“I used to be so jealous of them,” Olivia continues squeezing Ayda's tits and grinding her hips. “So big and bouncy. You'd walk around the house Miss Bombshell with hir big ol' boobies hanging out of hir camisole. And there I was, a flat little girl.”
Ayda opens hir mouth to counter but is interrupted by Olivia continuing.
“And I know, I know that was dumb. I was a little girl, of course I was flat. I think maybe it was misplaced possessiveness? Like I wasn't jealous that you had big boobs and I didn't, I was jealous that everyone got to see them and they weren't just for me, or something. I was stupid.” Olivia lifts the hand still held by Ayda from her big sister's breast, and moves Ayda's hand to her own chest. “And I'm still flat, but Sis? The way you look at me? How could I still be ashamed of my body with the looks you give me, the way I can feel your eyes on me, the way you pitch a tent every time you look at me?”
Ayda's heart swells.
“Come here, Livie,” shi says, as shi tugs the pup down into a passionate kiss. Soon their tongues are dancing, breath mixing as they pant and moan into one another's mouth. Olivia's movements become more forceful, more intentional.
“You're so fucking sexy.”
“Tell me more, big sis.” Olivia grinds down hard.
“Everything about you is so cute, fuck. Your tits! I love your little tits. They're so small, they're the perfect shape and size. And your nipples are so—” 
Hir breath hitches and shi presses up into the smaller wolf, 
“—so perky. I wish you'd go topless all the time so I can just watch your tits as you move around and stretch and just live. You're so small, so slender! But there's muscle in there, so taut and capable. I wanna squeeze your butt every time I see it.”
Ayda is gripping hir little sister tightly, alternately by her hips and by her butt, and thrusting up to meet her with every hump.
“And your pussyyyyy!” Shi nearly wails the word, drawing out the final syllable through gritted teeth. “It's so puffy! Such a cute cookie! I wanna squeeze it!” Shi groans. “I thought I'd cum in the shower just from my first look at it!” Shi's panting rapidly. “Then you shoved it in my face and it took all I had not to dive right in.”
“I wanted you to.” Olivia whines out. “I thought that would be it, and you'd fuck me right there in the shower.” Each of her pants is coming out like whines now
“And then I stood up, and dragged my cock against you, and I almost caaaaame,” 
“Me too, big sis! I almost—Aaa!” Their humping has become erratic. Drool drips from Olivia's hanging tongue to pool between Ayda's tits as they bounce from the ferocity of hir upward thrusts. “I almost asked you to let me jerk you off in the shower, before you offered to wash me.”
“I'm glad you didn't, baby, I'd've embarrassed myself even more than I did in bed earlier. Ah! You're so! Fucking! Tight!” Their thrusts are becoming more difficult to separate and return. “Why are you getting tighter? Fuck, Livie, it's my knot”
“Knot me knot me knot me knot meeeeeeeee!” Olivia cries.
With a final, forceful upward thrust, Ayda gets hir knot into the tiny spade just in time for it to finish inflating.
“We're tied, Livie! Fuck!”
Then in one voice, they both call out “I'm cumming!”
They both howl in unison as they achieve orgasm together. Olivia vibrates in her position atop her sister's hips. Ayda's balls draw up as shi pulses wave after wave of cum up hir cock and into hir sister's tiny vagina. The seal of Ayda's knot and Olivia's lips holds tight enough for the gushing cum to force its way into the pup's womb, filling her up and then some. Just before Ayda finishes, the pressure becomes too much and cum pours out of Olivia's little spade to join the pool of Ayda's pussy juice between hir legs and under hir butt.
Olivia's hands move to cradle where her lower belly has distended just barely from all the cum packed into her womb.
Between pants and gasps for air, Ayda chokes out “I love you, Livie.”
“I love you too, Ayda.”
“You okay, babygirl?”
“Better. Better than okay. I love you big sis.”
As they lie together, basking in the afterglow, still tied, the occasional twitch or flex causing another small pump of cum into the wolf pup's already-overflowing vagina, they share pillow talk. With her head once again pillowed on one of Ayda's tits, Olivia asks.
“I've been wondering, have you ever fucked yourself?” That gives Ayda pause.
“Like, put my own dick into my own pussy?” When Olivia nods into hir boob, Ayda hums and continues. “Yeah, but my balls got in the way, and the harder I got, the more uncomfortable it got having my dick at such a weird angle, so I couldn't really do anything with it. Probably for the best. I was still a kid, and had not yet learned contraception. Imagine if I'd knocked myself up.” Shi pauses for a moment, then hir eyes shoot open. “Shit! Speaking of, are we safe?”
“Yeah, Sis, we're safe.”
Ayda sighs and relaxes again. Olivia doesn't.
“I can't believe you didn't think about that. Seriously? You had a big, super-involved plan to get to fuck me, and you never even considered? You goober!” She pokes Ayda in the side, causing hir to flinch away from the ticklish sensation. 
Both wolves hitch and moan from the sudden stirring of their conjoined loins, then devolve into giggles.