Samantha only woke up in the morning when Steven, her boyfriend, called her from the bedroom door saying that breakfast was almost ready. She didn't get up right away, but thought for a while about a strange dream she'd had, in which she was a shemale who had a big dick and balls and had jerked off with them.
While remembering her 'dreams', Samantha felt a strange movement under the blanket and, wanting to see what was there, she lifted it she saw that she really had a cock and the member was pulsing hard with excitement between her legs, it has the cum dirt dry and the characteristic smell as well. She then realized that what she was remembering had been real.
She believed it was the effect of her boyfriend's pills that she had swallowed and would continue with the male member between her legs until the effect wore off, but even so she was very horny and didn't want to appear in front of Steven displaying an erection. With that she started stroking her 9 inch cock with one hand and groping her balls with the other.
Samantha was enjoying the feeling and didn't even worry about the time, so much so that she was startled when Steven opened the bedroom door again and came in asking if she was going to wait for breakfast to cool down before coming down, only to notice with a shock that the his girlfriend had a much bigger dick than his now and was jerking off.
"Hi Steven, your pills really worked." Samantha said
"I can see it but this big dick is in the wrong place, it should be between my legs when I fuck you." Steven said
"I know, but at least it's an interesting experience for me to come as a man. I want to take advantage of this before the pills wear off and I change back to normal." Samantha said
They hadn't realized yet that a mutation had already struck Samantha while she was sleeping and her precum gave off a scentless pheromone that made anyone around her crave for her cock. Unexpectedly, especially for Samantha, Steven got in front of her and reached down, taking her hands off her own cock and starting to suck it.
"Why are you doing this Steven? Are you gay by any chance?" Samantha asked
"Of course I'm not but, I can't understand either. I've never had any interest in anyone else's dick, on the contrary I've never liked to see it, but your dick is different and I feel very attracted to it, I just can't resist." Steven said and, before he could put his mouth back on his girlfriend's dick, she came by squirting a lot of cum in his face.
Samantha was a little panting and catching her breath as she recovered from her orgasm and waited for her cock to go soft or disappear for good, returning her vagina to its place, but it didn't. She felt the member throb strongly and together with her boyfriend watched the member, which was still hard, get even bigger as it grew another 3 inches, her balls also growing to match.
"It wasn't supposed to happen. Sometimes the dick stays hard even after cumming, but it never gets bigger." Steven said
"I can't go out with my dick like this and, I can't think of anything else, I want to come again." Samantha said
Steven then took one more attitude that he couldn't understand. He undressed and sat on the tip of his girlfriend's dick, pushing it to penetrate his ass. He hated the idea of a man getting his ass fucked and that Samantha's cock was too big for him, but the urge to have her male genitals inside him was simply irresistible, which her lack of resistence helped.
Samantha fucked her boyfriend really hard, all her inhibitions having been removed under the effect of the mutations caused by the pills, and because of that even though she noticed her cock growing even more inside him, she didn't see a problem and continued as if nothing was happening. Lucky for them one of the mutations caused Samantha's precum to affect Steven's body and allow his ass to stretch enough that he wouldn't be hurt by the size of her growing cock, even though she eventually couldn't push it all inside anymore. Her balls also overgrown, getting big enough to reach her shins. Such an increase in size forced Steven to step on her balls and get as low as possible on her cock, which had stopped growing to three feet long and the thickness of a pet bottle.
This way they continued without anyone noticing Samantha's breasts growing to the size of watermelons, her ass expanding and her hair changing color to blonde.
Soon Steven heard his girlfriend moan and once again push as much of her cock inside his ass as she could, then he felt a heat seeping through him, which meant she was coming and filling his insides with her cum, which brought him to his own orgasm. His belly swelled with the amount of cum inside him to the point that, when her orgasm subsided and he pulled off her cock, he looked like he was about to give birth to twins.
"This is sooo goooood. I loved fucking you and I can't wait to do it again, but it made me really hungry and I want to eat something first. You said breakfast was ready, didn't you? Let's eat then." Samantha said and got up, heading out to the dining room to have the breakfast waiting there, bobbing huge breasts, full ass and huge balls on the way.
The couple ate together and Steven had to help his girlfriend a little, as one of the mutations left her dick in a state of permanent erection and hindered her.
After having breakfast, Samantha wanted to fuck her boyfriend again, but he convinced her to seek medical help, as the effect of the pills should have worn off. Because they were both dirty with dried cum on their skin, they decided to take a shower first. Since they were already naked, they went to the bathroom together to wash up, but it wasn't as easy as expected. When they were both finishing washing Samantha, who had been unconsciously stroking her cock, came, leaving them both entirely white with her cum. Thanks to the new wave of cum they had to clean themselves again before getting out of the shower.
"Steven then went to his room to get some clean clothes to wear and go with his girlfriend to the hospital, but he didn't pay attention if she had accompanied him and was surprised to hear her screaming "Hey Steven, what are you waiting for? Let's go." Samantha's voice came from outside and so he quickly looked out the window, where he saw that she was already on the lawn in front of the house, completely naked, waiting for him.
"What do you think you're doing walking out of the house naked? Go back in here and put on some clothes." Steven said
"I don't want to wear anything and I don't even mind going naked. It's also not like there's any clothes on your wing that would fit me." said Samantha, which one of the mutations affected her personality making her an exhibitionist.