I picked up some lunch on the way back to Emily’s and let myself in when I arrived. I saw a pile of luggage and a wooden sled piled next to the door, so I assumed Emily’s change must be finished. I called out her name and heard an «in here!» in response. I wandered to Emily’s extra bedroom which she used as an office and very, very rarely as a gym. And that’s where I saw her running on her treadmill. From the waist up, Emily was her normal self, medium sized breasts bouncing with every step. From the waist down, though, Emily was greatly changed. She now had four legs attached to two sets of hips… separated by a kind of extra torso between her front and rear legs. She looked a lot like a centaur, but made entirely out of human components. All four legs were churning with the effort needed to hold her in place on the speeding treadmill. I walked into the room and circled her a bit, and saw that she had a pussy between both her front and rear legs and that she had a long, horse-like tail of hair growing from her tail bone above her butt and rear legs. Emily smiled happily at me as she puffed on the treadmill.
She bent her legs and launched herself up in a vertical leap that carried her sideways off the treadmill. «Tah-dah! I’m a humantaur a-leaping!»
«Yeah.» Emily gestured at her top half «human» and the her extended lower half «taur. Simple.» She capered around in a circle, showing grace and mastery of her four-legged form. She turned her butt my way and wiggled it and swept her tail back and forth, flipping it up and giving me a tantalizing glance of her rear-sex. She glanced over shoulder and bat her eyelashes at me. «Do you like it?»
«I love it!» I could feel myself stirring in arousal at the thought. «But when do we have to get going? I packed my car and we should be able to fit everything and the extra you if we push the seat back…»
«Oh, we aren’t going anywhere until the morning.»
«So what do you have planned for tonight?»
«Just this.» She trotted forward, circled me in a hug, and gave me a long, slow kiss. I wrapped my arms around her and kissed her back hungrily. She unbuttoned my clothes while still making out with me and slipped if off my chest. Arms free I grabbed her breasts and squeezed them as we made out. She pushed me toward the desk in the office, pushing me onto the edge and kneeling with her front legs to tug off my pants, her rear legs and ass still swinging invitingly in the air. My pants off, Emily took my cock in her mouth, pumping a hand on the shaft of my cock and gently squeezing my balls. I groaned happily. Emily soon (too soon!) let my cock escape her mouth and raised herself up to kiss me, which we did for a bit until I lifted her forelegs and planted them on the desk behind me and ducked down, burying my face in her fore-cunt, kissing and licking and sucking and enjoying the tangy musk of her cunt. When she started to pant and whine above me, I lifted my face and climbed to my feet, and Emily lowered herself so she was kneeling on the desk, straddling my lap. I pushed myself inside her vagina, and chest to chest, Emily braced on the desk and her rear legs, arms circled over my neck, I began to thrust into her, falling into a comfortable rhythm. Emily moaned loudly, and started to thrust back toward me using her hind legs, driving us together faster and faster and with more force until, clutching my back, she groaned deeply and tensed in orgasm. I finally relaxed holding in my own orgasm and came inside her fore-cunt.
I laughed happily and pulled out of her, but she was still flushed and panting. «Ian… are you… okay to go again… already?» Emily gestured at her hindquarters. «I… I’m not done.»
I circled her body and sure enough her tail was still raised and her rear pussy was still sopping and swollen with arousal. I slipped two fingers inside it, and slowly started to stroke it, while I used my other hand to rub some life back into my own
softening cunt. Emily, meanwhile, was stroking her breasts and slipping one hand down to finger her fore-cunt. She moaned and pushed back against my hand. The feeling of her hot cunt and the image of her masturbating in front of me had my cock stiffening again. As it came erect, I didn’t waste time and slid it inside her hungry cunt. Clutching her surprisingly muscular ass, I began to thrust inside her, deep long thrusts that made Emily gasp. Feeling a little insensitive from having cum moments ago, I thrust deeper and harder and faster, trying to push myself to another orgasm. Emily strained against me solidly planted with her four legs and frisked me with her tail as it began to swing and sway erratically as orgasmed and orgasmed again. I felt myself getting close, and thrusted even deeper and more forcefully, causing Emily to squeal and shudder as she orgasmed again. And then, finally, I felt myself coming again.
I collapsed against her horizontal new back. «Phew! That was great!» I finally managed to pant.
«Y-yeah» Emily panted back. «You’re a real stud. But…»
«You were gah-great, but mmm, I think it would be fun, to be… filled on both ends… Maybe we can try some toys next time?»
«Oh… I think I have a better idea.»
It took a couple hours, but the doorbell finally rang. I opened the door and in stepped Meredith, wearing a dark grey trench coat, tights, and patent leather slingback heels. Emily peaked from around the corner, hiding her transformed body and nakedness.
«This is my friend Meredith.» Meredith smiled shyly and waved a little.
«She’s a reporter, and when you started transforming, I uh, asked her if she knew anything about what you were doing. She looked into it and well…»
«I found them.» Meredith said happily as she slipped off her coat revealing that aside from her stockings and shoes, that she was naked under the coat. Which showed Emily her three large breasts and the stiffening cock on her crotch.
Emily walked around the corner, heedlessly revealing her naked, four-legged form. «You got a bunch of trial vials too?»
«Oh no,» Meredith purred, hefting her outside tits, «these are mind for keeps.»
«Wow….» Emily breathed, getting a worryingly distant and hungry look.
«Anyway.» I said, trying to recapture the moment. «Meredith is here to help us get you what you want.»
«What do you mean?»
«I think he means this.» Meredith said as she swayed over to Emily, clutched her neck and drew her down for a deep kiss. Emily kissed her back, hands raising to grasp her triple breasted chest. Meredith’s cock swelled, and bobbed slightly with her heart beat. Emily reluctantly broke the kiss and both women looked at me. I smiled lecherously and nodded, walking over, placing my hand on Emily’s taur back, and tracing my way to her rear-sex.
By the time I reached Emily’s rear pussy, the two women had re-engaged with each other, kissing hungrily and clutching at each other’s breasts. I felt myself come erect at the visual of lover and one of my best friends making out. (I guiltily admit that I have had dreams like this…) Emily purred and reached down, grasping Meredith’s penis in her hand, making the other woman gasp and jump a little, like a teenage boy unaccustomed to having someone else feel their penis. I grinned, and kneeled down, burying my face in Emily’s hind-sex, her tail draped over my back, constantly frisking. When I felt Emily tense, and thrash in orgasm, I lifted my face and saw Meredith with look of rapture on her face as Emily had leant forward, nearly horizontally, to suck on my friends cock. Meredith was panting and tensing on her feet and I was worried she was going to cum prematurely, so I swatted Emily’s butt, getting her attention as she came off Meredith’s cock. Meredith surged forward hungrily and, with some help from Emily, slid her cock inside Emily’s fore-sex. Emily wiggled and moaned at the penetration. I let the two women to kiss and thrust a little
for a moment before I pushed my cock into Emily’s rear-sex, and began to slowly very slowly thrust. Before me Emily was whispering instructions to Meredith, coaching her to thrust slower and deeper, matching my rhythm. I slowly began to speed up, and Emily instructed Meredith to match me. I went faster, and so did she, and faster and faster, and soon Emily was being fucked hard from either end by two living cocks like I knew she wanted. Emily tensed and howled in orgasm! And again! And again! And Meredith lost control of herself and clutched herself to Emily and ejaculated inside my girlfriend. I kept discipline though and managed to drive Emily to one more screaming orgasm before I pressed myself as deeply as I could inside Emily and erupted inside her.
The three of us collapsed in a happy, panting tangle of limbs, Emily mewling happily, and Meredith with the blissed out look of someone who had just lost their virginity.
I laughed happily, «Meredith, let me know when you’re ready to switch sides.»
Emily made a mewling-squealing noise in glee.