Alva Janz

Alva Janz writes contemporary sci-fi and paranormal erotic fiction involving body transformation, including gender-swap, futas, hucows, and more.
All of Alva’s erotic stories are intended for adult readers 21 and older, and contain explicit language and sexual content.
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Futanari

How I Became A Futa At The Gym

Female to Futanari Rapid Body Transformation
[ Book Cover: How I Became A Futa At The Gym ]

When a beautiful, fit, and muscular woman with a very large bulge in her leggings walks into the university gym while I’m working out, I can’t help but become extremely curious.

When I ask, she tells me she’s a futa, and proves it. Then she says she could turn me into one, too. All it will take is for us to do it in as many ways as we can, right here in the gym! I’m so intrigued that I can’t help but take her up on her unbelievable offer.

Once we’re done, we discover that my futanari transformation is already beginning. So she helps make sure my new endowment grows as large as possible, right before my own eyes. And I definitely do seem to just grow, and grow, and grow.

Now with my own enormous new equipment hanging between my legs, a sexy encounter with three curious strangers on the subway reveals that my life is never going to be the same, in all the best ways.

And once I get home, my roommate Cheryl’s life might also never be the same, after she expresses interest in learning what it’s like to become a futa herself…

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[ Book Cover: How I Became A Futa On Halloween ]

It’s Halloween, and me and my two female roommates are on a mission: take the sexiest Halloween photo to enter into a competition at our college’s student costume party later this evening.

I suggested that we go to the same all-male gym where last year there were sexy trainers dressed like vikings. But when we get there, the gym is closed and all we find are a bowl of pills apparently promising male enhancement.

What a joke! But then, it is ‘trick or treat’ after all, right? But only a little while later I start growing a new male appendage.

Over the next few hours it becomes longer, thicker, and fully functional. My roommates are initially shocked, but soon they both warm up to my bodily changes.

With my new addition and above-average capabilities, maybe we’ll have a chance at winning that photo competition after all! My surprising futa transformation might even attract me some hot male attention before the night is over.

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Gender Swap

Her Midnight Masculinity

Gothic Female to Alpha Male Gender Swap Body Transformation
[ Book Cover: Her Midnight Masculinity ]

My friend Lindsey and I are browsing an estate sale when we come across an ancient book written in Latin. One amusing phrase catches her attention, and after I read it as a joke, we head back to our dorm.

Yet later that night, I’m shocked when I wake up and discover that I’ve become a man! And not just any man, but a tall, muscular, and very well-endowed gothic alpha male.

Lindsey is just as shocked by my transformation as I am. However, she figures we might as well make the best of the situation by enjoying my new male capabilities. And we certainly do.

The next morning, I’m back to my female self. Thinking that it’s all over, I look forward to going out to a club that night with Lindsey and the rest of the women in my dorm. Yet once the clock strikes midnight, I begin to feel my body changing once again…

All I can hope is that there’s some way to undo this enchantment before my gothic boyfriend Jordan finds out about my new alter-ego!

Unless it turns out that he, too, might enjoy it if I were to become a big, strong, excessively well-endowed man every night from now on…

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[ Book Cover: A Mad Scientist Turned Me Into A Fertile Bimbo (With A Secret): Justin’s Story ]

With the house next door up for sale, I knew I’d be getting new neighbors sooner or later.

But I didn’t expect them to be a retired scientist and two extremely hot younger women. Yet both women have an astounding secret—they were once men! They even still have the equipment to prove it.

It’s all thanks to the old scientist’s secret gender-bending research. And now, he wants me to do my part to help him take his experiments even further.

As strange as it is, I’m extremely interested in the scientist’s proposal, and I even try a small dose of his experimental serum. To my surprise, I quickly grow an impressive pair of curvy assets.

Although the feminine changes I’ve undergone make my life somewhat awkward, I’m craving even more.

I just need to keep my bodily changes hidden long enough to finish an incredibly important presentation at work. But when I can’t, our foreign investor suddenly becomes far more interested in me!

To demonstrate the full potential of this research, I volunteer to let the mad scientist transform me into the woman of my dreams. Then we’ll see if I’m able to become a mother

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[ Book Cover: Nerd to Fertile Bimbo (With A Secret): Simon’s Story ]

All my life, I’ve been teased for being a nerd. My rather un-manly body doesn’t help. So the fact that the other guys at the pool make jokes about me isn’t surprising. But one particular joke about me being a sexy woman just won’t leave my mind, and excites me in a way I’ve never known before.

When I go into work the next day at the laboratory where my research team is developing a new medicine to help aging women, I’m suddenly tempted to see if my new fantasy could become a reality. However, an accident causes me to ingest far more of the potent medicine than I expected.

Within hours, I’m becoming noticeably more feminine. The guys at the pool are the first to see my bodily changes, but they quickly come to appreciate my new female assets.

With a little help from a new female friend who loves my remaining male attributes, my wardrobe soon matches my new feminine body.

Strangely, I also notice that I’m developing new cravings for my well-built male boss. To my surprise, he also wants to see just how feminine I can become!

After a second large dose of medicine, the bodily changes I undergo thrill not only myself, but also all the men in my life. But my numerous encounters mean that I have no idea which man is the father of the multiples growing in my womb...

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[ Book Cover: Jock to Fertile Bimbo (With A Secret): Steven’s Story ]

Looking to make a little extra cash, I spot an ad asking for experimental test subjects at my college. Unfortunately, the scientist tells me he’s only looking for female volunteers. As a muscular male football player, I’m not qualified.

But Dr. Gibson proposes another experiment that I’d be perfect for. He’ll even share half his grant money with me! However, if the treatment is successful, I’ll supposedly become a woman. He hopes I’ll also develop all the right parts to become fertile!

Surely such a change is impossible, even if the idea is strangely arousing. Still, all that money is too tempting to ignore.

Sooner than I ever expected, I can’t hide my bodily transformation from my male roommate, my coach and teammates, or my classmates.

Yet even when I become the hottest woman I’ve ever seen, there’s one part of myself that I’ll have to keep secret, since it shows no signs of disappearing.

After the surprisingly-successful treatments and all that I’ve experienced with my new body, now I’ll only have to wait nine months to see how big I grow

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Hucow

[ Book Cover: I Became My Professor’s Hucow ]

As one of my university’s few female biochem graduate students, I’ve just been assigned to work part-time with one of the sexier male chemistry professors.

Sure, he’s got a reputation for attempting to produce a formula to enhance the size and productivity of women’s nourishing assets. Although few people take his work seriously, I think it’s an honorable goal.

Yet, as I work with his formula, I can’t keep myself from wondering what the results would be if I tried it myself. This temptation leads to accidental self-experimentation which makes my nearly-flat chest start growing bigger and curvier.

At least it seems that I’m now getting the attention I’ve always wanted from men. It might just open up a new career path for me, too.

However, I have no idea how my professor and my female best friend will respond when they see the gigantic changes that have happened to me, and how hyper-productive my body has become...

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[ Book Cover: Becoming My CEO’s Hucow ]

I’ve always wanted bigger feminine assets. Now that the pharmaceutical company I work for is almost ready to launch a new product that promises to enhance them, I can’t contain my curiosity.

After trying a stolen sample, I notice results faster than I ever expected. But so does my CEO, when an embarrassing incident happens during my important marketing presentation.

I’m mortified, but to my surprise, he’s thrilled with these results, and so are the R&D staff. In fact, he wants to make me even bigger and more productive, and then take me to a trade show to demonstrate the product’s effects to potential investors.

As much as I love my newly enlarged and hyper-productive assets, is his business all that my CEO cares about? Or is there a chance that he’s interested in a more permanent relationship between us?

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Other

[ Book Cover: Four Scoundrel Ghosts and the Vicar’s Daughter ]

Agnes’ father, the town vicar, has fallen ill. It’s now up to Agnes to perform a ritual to satisfy the unruly ghosts haunting the church’s undercroft, in order to prevent them from causing chaos in the town.

However, the ritual only works if she is “pure in heart.” Having recently stolen an altar candle and used it to satisfy her sinful lust, she is unable to successfully complete the ritual.

When four ghosts of deceased male scoundrels appear to her, they suggest an alternate way in which she can satisfy them. Despite her inexperience with men, Agnes is willing to give it a try since it’s the only way to avoid having to confess her secret sin.

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[ Book Cover: Cuckold, Wife, Bull, Dominatrix ]

Kenneth’s been a cuckold for five years. While initially exciting, now it’s losing its novelty, both to him, and his sexy wife Valerie. He’s open to almost anything that could re-ignite his cuckold angst.

Their long-time bull, Brett, has a plan. Under the supervision of Brett’s Russian dominatrix girlfriend, he will introduce Ken and Val to BDSM by dominating them both in Katya’s prison-themed dungeon room.

Ken will even try a new toy in an unexpected location. But the rule is: each time Brett brings Val to climax, the toy gets bigger.

If this is not enough, will Ken have the courage to go through with the final humiliating activity that Brett suggests?

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