Emily and Chrissy go home together

Emily and Chrissy spend the rest of the work day writing up reports on their findings. The excitement for both the project and their relationship is palpable. As the work day winds to a close, Emily makes a proposition.

"Wanna get dinner together?" She asks Chrissy. "Maybe come back to my place after." She adds, making her intentions clear.

"I'd love to." Says Chrissy. "Is this fine, or should I go home and change?" She asks, gesturing at her clothes.

"I think you look perfect." Emily assures her, followed by a quick kiss.

They travel together to a nice restaurant and get a table together. "To us." Chrissy says, holding up her glass.

Emily clinks her glass with Chrissy's. "To us." She echos. "And to the future of humanity."

Chrissy giggles lightly at how serious that sounds. "You know, last week I never would have guessed I'd be having dinner with my boss, while dressed in women's clothing, before heading back to her place to see if she can breed me." She swirls her drink before taking another sip. "And it's only Tuesday."

Emily smiles bashfully. "When you put it like that it sounds like we're moving a bit fast."

"I like it." Chrissy assures her. "It's like everything I was yearning for started happening at the same time. You and I are dating, we created a working serum, and I came out as a woman. This is awesome!" She downs the rest of her drink in celebration. "And thanks to your magic sperm I don't even have to work to look feminine; between my face, voice, and breasts I couldn't pass for a man if I wanted to." She says happily, glancing down at her chest to admire the modest cleavage visible down the top of her blouse.

"Well I'm glad you like it, because if you come home with me tonight there's a good chance you'll lose every shred of masculine development you've got left." Emily warns.

"Promise?" Chrissy pleads cutely.

They finish eating and head excitedly back to Emily's place. "Have you had sex since your pussy grew in?" Emily asks as they travel.

Chrissy shakes her head no. "Only a bit of oral." She says meekly. "And it was with you earlier today."

"Does it make you nervous? We don't have to do any penetration tonight." Emily says with a touch of concern.

Chrissy shakes her head again. "No, I want to try it. I haven't done it with a partner yet, but I love penetration when I masturbate, and I really want to feel your cock inside me." She admits lustfully. "What about you? Nervous to fuck me?"

Emily smiles. "Not at all. I want it so bad I can hardly think straight." She confesses. "My whole life guys have made it sound like the pinnacle of pleasure, the best feeling ever, but I could never experience it for myself. I would get so jealous sometimes, watching the absolute joy on a man's face as he entered me, wishing I could know what it felt like for him."

Chrissy grins as she reminisces. "It is a pretty wonderful feeling. I hope my pussy lives up to your expectations."

As soon as they get to Emily's place they can't keep their hands off each other. The two make a bee-line for the bedroom, shedding their clothes along the way. Emily helps Chrissy take off her bra and pushes her naked body backwards onto her bed.

"Is this what you want?" Emily asks, stroking her fully hard cock. Chrissy nods enthusiastically, spreading her legs for her lover. Emily kneels on the bed, getting in position to penetrate. She uses the head of her cock to stroke Chrissy's slit, spreading her wetness around and thumping the fat tip against her clit. "Even though I could get you pregnant?"

Chrissy nods harder. "That makes it even better." She moans, bucking her hips to get more friction against Emily's penis.

"Let me know if it starts to hurt." Emily says, lining her dick up with Chrissy's soaking wet entrance. She pushes gently at first, applying gradually more pressure until the head of her massive cock slips into the hot canal of her lover's sex.

"Holy shit." Chrissy gasps, feeling her pussy stretch around Emily's throbbing member. "You're so big."

Emily smiles. "You can take it, I'll go slow." She reassures her. She begins rocking her hips, causing her dick to slide in and out, pushing it a little deeper with every thrust. "You were right, this feels wonderful." Emily sighs as she savors the sensation of her cock inside Chrissy's pussy. "I could get used to this."

"Me too!" Chrissy pants breathlessly, completely overwhelmed by the things she's feeling. "Fuck, I love the way you fill me up."

Emily begins to thrust more forcefully, burying the entire length of her dick inside Chrissy's trembling cunt. "Get ready." Emily warns, feeling her balls tensing up for a massive load.

"I am!" Chrissy cries out. "Oh fuck, I am!" She moans, beginning to orgasm on Emily's cock. As Chrissy's pussy spasms in pleasure it triggers Emily's orgasm, causing her cum to spurt deep inside, flooding her insides with potent sperm.

Emily continues to pound into her lover, pushing her cum even deeper as Chrissy's pussy milks her cock. Before Chrissy's first orgasm ends another one begins, this one brought on by a reaction of the nano-virus.

"Don't stop." Chrissy pleads. "The changes are starting. It feels so good!"

With each thrust Emily can feel subtle signs of the transformation. Chrissy's hips are getting wider while her ass and thighs plump up. Emily gives a particularly firm thrust and hears a crack as Chrissy's bones shift.

She can tell from the way Chrissy's pussy clenches around her dick, and from the way it makes her moan, that the cracking was immensely pleasurable for her partner, so she keeps up the pressure, causing her lover's joints to pop and crack orgasmically again and again.

By the time the transformation is winding down Emily is exhausted. She rolls off of Chrissy, her dick finally beginning to go soft. Chrissy is also exhausted, panting for breath and covered in a thin sheen of sweat.

"That was way better than the first time I lost my virginity." Chrissy sighs, running her hands over her newly shaped hips and thighs.

"Same." Emily agrees, snuggling up against her lover. "I think this cock suites me."

"I certainly appreciate it." Chrissy agrees, turning onto her side so Emily can spoon her.

"Wow babe, you've got a bubble butt now." Emily says, squishing against it. "Did you get shorter too?"

"I don't know, maybe. It felt like a big change." Chrissy steps to her feet, stumbling a little as she finds her new center of balance.

Emily turns on the light and gasps. "You did get shorter, and your limbs changed too." She says, examining Chrissy's now-slender arms and shapely thighs. "It looks like your hands and feet have changed also." She adds.

Chrissy does a little twirl to show off her body. "I love it, I feel so cute." She enthuses.

"Even though you're shorter than me now?" Emily asks.

Chrissy nods. "I like being smaller, it makes me feel more feminine."

"You really are a woman." Emily replies, giving her a healthy pat on the rear.

"Yep." Chrissy says happily. "Before long I'll even be a mom."