"look at this!" Jessica said by typing a few things and then pressing the Enter key. In that exact moment Nikki's cup size inflated from a pair of D cups to DD.
"What the!" Nikki gasped feeling the pressure her new breasts exerted in her bra, Jessica grinned at her. "Okay, okay I admit it" she raised her arms, "you were right about this, so what do you have in mind?"
"Well... I wanted to experiment this with you at my side, so why not merging together as a little experiment?"
"Oh! We can be a two headed human" Nikki said as she read many sci-fi stories and fan fictions where characters fused. "I want to keep it that way, if our heads merge too our minds could turn into one and go crazy... Not so fan of that"
"Sure I'll keep that in mind" Jessica selected a merging setting on the computer and selected herself and Nikki, then she stood up and stretched. "We have to be naked for this by the way, I don't want any damages in our clothes or possible accidents." Nikki nodded taking her words casually.
Both girls stripped down all their clothes, not being ashamed since that wasn't the first time they saw the other naked, Jessica showing her white caucasian body as Nikki revealed her completely tan body (including her chest and crotch). Jessica envied her roommate's DD cup boobs, even that they were modified a little by the Chronivac she couldn't believe the difference, looking down at her flat A cup chest. But soon that would change...
"So now we just hug or something and we merge into one?" Nikki asked.
"More or less. You turn around so I'm facing your back, then we come together."
Nikki did as her friend commanded, then Jessica approached her closely. "Now just step back into my feet... Oh~ that's right."
"Uh, wow, that feels strange." Nikki commented with surprise. Jessica smiled.
Looking down at their now merged legs she noticed their current fused body parts were turning into Jessica's skin colour, not even a combination of both skins. "Umm... I can't feel our legs ." She said anxiously.
"Don't worry, you'll get more of yourself further up, see?" Jessica tried to calm her as their pelvis fused, resulting in their crotch area paint itself by Nikki's tan tone. "You're getting the middle too."
"Will I keep my head? What about yours Jess? Won't one of our heads go numb too?"
"I promise you Nikki! Your head won't go numb, trust me, you'll enjoy this, now take my hands."
As their arms fused together Jessica used their hands to press Nikki's body into hers. It looked like Nikki's tan DD boobs were now attached to Jessica's chest, above their white skinned belly and abdomen. "Looks like you're keeping the tits Nikole~" She giggled while controlling their hands again to push Nikki's head down, forcing her head to be between her breasts.
"Jessica! What are you doing!?" She said suddenly alarmed.
Jessica chuckled. "You didn't want our minds to merge remember? So I've got to put your head somewhere." Jess continued pushing her friend's head down, passing her breasts and over her tummy.
"But, where!?" Nikki said as her head was going further down than her belly button.
"Right... here." Jessica said, letting her head come to a rest.
"Your crotch?" She said as it was the spot where her head stopped.
"Heh, nope!" Jess placed the tip of a finger on the button of her nose. "My pussy!" And with that she pushed what was left of Nikki's head and her nose in between their thighs. Her nose shrinking and her mouth reshaping into a vertical slit. Jessica began to feel hot as she teased her with her fingers but to Nikki it felt like her lips were tingling and whole head was buzzing and burning with hot blood swelling in her face.
A few seconds later Jessica stepped over to a full length mirror so they could see themselves. The result looked exactly like Jessica but with with a few key differences. Her chest had now Nikki's big DD cups while all her pectoral zone was tanned like her. The same thing happened to her crotch and waist, her white belly and legs blended into a darker skin tone when they reached that zone. And finally Nikki, who was reduced to be Jessica's vagina just having her pair of eyes above her vertical dripping "mouth."
Then Jessica took a long transparent white shirt and draped it over them kinda obstructing Nikki's view. "I wonder how long it'll take before our friends figure out where you are~" Jess teased "Until then it'll be our little secret. Then we'll see how long you can enjoy yourself before changing us back." She began caressing one of their nipples and could feel her lower friend getting hot again "Which won't be anytime soon~" she said as she walked through the room, feeling Nikki struggle between her legs.