Emily looks over Spencer's at me as Spencer peppers her breasts with light kisses and sucks. She smiles at me and then closes her eyes to appreciate the sensation and gasps as Spencer takes hold of a pert nipple and bites on it gently. I'm leaning naked against Emily's desk, considering what my next move should be. Spencer seems to just be going with her instincts but I like to think things through a bit first. I want Emily to be really ready for what we're planning on doing tonight. I watch them for a few moments more, almost allowing myself to be distracted as Spencer starts groping Emily's bottom, before making a decision.

I stride forward confidently and put my hand on Spencer's shoulder to signal I want her to stop. Then I take hold of Emily's hand and lead her to the desk I have just vacated. I position her against the desk and run my hands down her front, checking to see how turned on she is. Judging by her reaction she's pretty far gone already – partly from anticipation and partly because she's just like that in general – and she arches into my touch. I reach between her legs and am unsurprised to find her sopping wet. I step back and motion for her to turn around before trailing kisses all the way down her spine until I reach the exquisitely soft skin right at the bottom of it. I lick at it gently, smiling as she gasps in response. I love all the little spots of sensitive flesh on her body and have practised stimulating all of them. I never get bored of it. I could do this forever. I run my hands along her sides and then up her back until I can place my palms against her and push gently, signalling her to bend over. She obliges and settles onto the desk as I continue to kiss the very top of her spine where it meets her ass, dipping my tongue into the little hollow where her cheeks meet.

She knows what's going to happen next. I can hear her holding her breath, concentrating on what I am doing. I can also see that she's sticking her ass out slightly, inviting me in. I draw back, again, to admire her ass and let my hands wander. I squeeze at it, stroke the back of my fingers along the curve of her cheek, run my fingernails across it as she stands there patiently, letting me take my time. I put my palm flush against it and I can feel her warmth. It makes me want to speed up.

I lean forward and kiss her cheeks all over, nipping lightly, licking in places until my mouth is watering. I kiss where her cheeks meet and work my fingers around to her front to gather some of her cunt juices onto them. With my other hand I grope her cheek, pulling them apart so she's open to me. My hand comes up and I stroke my soaking wet middle finger all the way up her, allowing her own juices to lubricate her delicate opening.

I put my hands on both of her cheeks, holding her open as I lean in further and take my first tentative lick. We've done this before, quite a few times, but I'm always a little nervous at first. It turns me on so much but I always want to make sure Emily is as comfortable with it as I am. She genuinely grunts at the first contact my tongue makes with her asshole and I lose focus for a minute as I take that as permission for a firmer stroke. I run the flat of my tongue up and over it, slowly, recognising the taste of her cunt but how different the flesh feels. It's firmer, puckered, more tense. I love it, and I reckon she's pretty keen on it too since she grips the edge of the desk and lets out a moan.

I go in for another lick, this time with the tip of my tongue and push against her entrance as I pass. She gasps and her legs jerk as she struggles to keep herself up. I start licking in earnest now, no longer experimental as my tongue swirls around her entrance and flicks against the sensitive nerves. Her cheeks are tense in my hands, I can tell she's seriously turned on and trying not to push her ass back into my mouth. I'll know I'll have succeeded when she starts doing that.

I increase the pressure and press my lips over her ring, enclosing it, switching to short, solid circles around and around. She jerks against my face again, gasping and grunting, as I settle the tip of my tongue in the middle of her entrance. I push slightly, feeling the muscle resist and then yield. I'm not going to fuck her with my tongue, we'll be doing plenty penetration later, but I want to suggest it and leave her wanting more. I wiggle my tongue, allowing her to feel the sensation in different directions and then resume long, drawn out licks up, down and around.

I lose myself to it and open my eyes to find myself gazing up at her back from between her perfectly round buttocks. There are a few views better than this in the world but they are also Emily, and this comes pretty high up on the list even so. This girl's ass is perfect. Just as that thought enters my brain, two things happen at once. I feel her start to push back against me, angling for more, giving in to the desire she has to be taken this way. Sometimes it takes her a while to relax and allow herself to want it, and I know that patience pays off in that regard. The other thing is a hand on my shoulder, pulling me back and reminding me that Spencer is being left out.

I pull away and look at Spencer, who is red in the face and simply gestures for me to look at the floor underneath us. I glance back and see a wet patch directly underneath Emily, and then raise my eyes to her cunt and her angry red swollen clitoris just in time to see a drop of her juices fall onto the patch on the floor. My eyes widen and my head spins as I take that in.

"I think she might be ready now, Paige," Spencer deadpans, her eyes never leaving Emily's middle.

"Em, you're dripping on the floor," I say, finally finding my voice. My own breathing is ragged and my heart is pounding in my chest. We've done a lot but this... this is something else. I cannot believe we are actually about to do this. I push myself up and put my arms around her, pulling her up and turning her in my arms. She looks less nervous than I feel which is incredible considering the situation. She looks excited, turned on, full of anticipation but I can tell there's a little concern there too; she doesn't know how to do this or who to go where.

Spencer and I have already sort of made a deal about this. She has a natural disposition for anal, for some reason, and I am perfectly happy taking Emily's front and getting to watch Spencer fuck her from behind, so it all worked out well. I imagine if we had disagreed on that crucial point we wouldn't be here now so I thank the heavens above that Spencer and I finally found something to agree on.

Spencer climbs into her leather strap on set, clumsy for a change as she's obviously nervous too. She walks over to the bed and Emily watches from my arms, her skin hot like she's on fire, her eyes dark. Spencer takes some lube from the bedside table and applies it liberally to her slim shaft. We picked it specially for this; wanting something that would be comfy for Emily but was a little more significant than the butt-plug we usually use. It's smooth and angled and I think it'll work just fine. She grips her shaft and strokes it up and down suggestively as Emily watches, breathing heavily. Emily moves away from me, leaving my arms empty, and goes to Spencer on the bed.

I hastily climb into my own strap-on, the shaft on this much more impressive than the one Spencer has. It's our usual dildo, bigger than the average, curved with wavy ribs running along it. By now, Emily is sitting on all fours on the bed as Spencer positions herself behind her.

I watch as she takes more lube and squirts it liberally in between Emily's cheeks. Spencer uses her fingers to spread it around before putting the tip of her middle finger at Emily's hole. I watch as she pushes gently, wiggling it slightly to allow the muscle to relax until the tip is past the tight ring and she's up to her first knuckle joint. I can see how tight Emily is, having not had any sort of anal play in a while. I can't tear my eyes away.

I watch as Spencer pushes forward again, pulling out and wiggling as she moves to make it easier. I see her reach her second knuckle before she pulls out and starts again, this time pressing in all directions to open Emily up. I watch as she buries her middle finger entirely inside Emily and I can see that she's moving it inside from the way the back of her hand moves. She draws out again and adds a second finger, still working slowly, until Emily is taking two of Spencer's fingers with relative ease. Spencer thrusts them in and out slowly a few more times, now being a little rougher than she was at first, before pulling out entirely and reaching for the lube again.

She applies more to her own shaft, and adds some extra to Emily just to be safe. As far as anal is concerned, there is no such thing as too much lube.

Spencer moves forward and I finally break my gaze from Emily's ass to look at her face. Her eyes are closed and she's gripping the sheets. She looks tense and I worry for a minute that she's not okay with this anymore. I am about to open my mouth to say something when her voice cuts me off.

"Spencer," she says, her voice a breathy pant, "slowly, please."

I wonder whether the please is aimed at asking Spencer to go slowly, or whether it's also her asking for more.

"I know, honey, I know," Spencer replies, her voice soft, reassuring. She strokes Emily's backside before parting her cheeks with one hand and taking hold of the shaft with the other. She positions its head at her entrance and allows it to rest there, only putting a little pressure. I am not sure if I have ever seen any of us more turned on in our lives. Watching them, and knowing what's coming next, has made me throb painfully. I can only imagine how Emily feels.

Spencer pushes forward ever so slightly, the head starting to stretch Emily's taut ring. Spencer is looking down with a determined, awe-struck expression and Emily has her eyes closed, biting her bottom lip. None of us are breathing. Spencer pushes forward again, slowly as possible, until the head slips inside and Emily lets out a guttural grunt I hardly ever hear from her.

"You okay?" I ask, even though I know Emily would say if she wasn't.

"Yeah, keep going," she replies, still somehow biting her lip.

Spencer stays at this depth for a while, pulling it back and forth, allowing Emily to get used to the size. She pulls out and then pushes in again a little more this time and I watch as she takes two steps forward and one step back until she's flush with Emily's backside and the entire thing has disappeared inside.

"Fuck!" Emily lets out. She only ever swears during sex, another thing I love about her. She pushes her ass back into Spencer, clearly loving the sensation, and maybe also the way their skin feels pressed together in this way. Spencer puts her hands around Emily and hugs her tight, pressing a kiss onto her back before straightening up and drawing out part way. We agreed she should fuck Emily a little with it first, get her used to that at least before another joins the mix, but that she shouldn't do it for too long. I watch as she thrusts slowly, the dildo sliding in and out. After a little while she stops and looks at me.

Holy crap this is actually happening. But why am I the one freaking out? Emily's the one about to get DPed and she looks calm as a cucumber at this point. She looks over at me too and smiles, that smile only me and Spencer get and I trip over my feet trying to get to her. The logistics of this is something we weren't quite sure about, but in the end we settled on me underneath with Spencer from behind. Emily pushes herself up so that there's room under her for me to crawl in and Spencer opens her legs so I can slide my own in between hers and Emily's.

I take the shaft of my own dildo and look down between Emily's legs. She's as wet as ever and I slide the head of the shaft through her slit to lubricate it. I position it at her entrance and push up with my hips, feeling it slip inside.

And then Emily sinks down onto it and I can feel her weight on top of me and I can see that my dildo is deep inside her and Spencer has closed any space left from all the shifting and we are both buried inside Emily.

We all stay still for a few moments, processing what's happening. I can hear Emily whimpering and I desperately wish I could feel what's going on inside her right now because she sounds pretty close to an orgasm. This particular kind of whimper is usually reserved for the end of sex, when she's come a couple times already and is about to have her big final.

She comes around and seems to focus on what is happening. She looks down at me, her hands supporting her on either side of my face. She gives me a half smile and struggles to get out her next instructions.

"I want you to start moving, real slow, it feels so intense. But only one at a time, okay?"

I look at her, and at Spencer behind her and find my voice again.

"Okay…"