I do not own YuGiOh! Nor it's spin-off series YuGiOh ZEXAL. The card game and franchise is owned by both Konami and Kazuki Takahashi.

...

"...Alright, what should I do now?", mused Jake as he contemplated the numerous boxes present in his living room. It had only been a few days since he moved in the new neighborhood, one that was known for being generally peaceful and quiet. Jake was glad he moved away from the busy city, and while he would miss seeing his parents and friends, he was also excited to see what new opportunities and choices would await him here.

Of course, he had to finish unloading everything first.

...

Jake groaned as he finished pushing another one of his boxes into his room, finally resting to take a breather before continuing.

However, something from inside the cardboard box slightly peaked the teen's attention, making him stop to see what the thing was. Upon taking the object out of the box, Jake was immediately hit with endearing nostalgia when he saw what it was.

It was a pack of YuGiOh cards.

"Heck yeah, I remember playing with these a lot back then", reminisced Jake back to those times when he played the game with his friends. Truth be told, Jake was a massive fan of the card game, and as a result bought a lot of figurines and other merch (whenever he could afford it, of course).

Of course, the teen was also a big fan of the anime series, especially ZEXAL. The spin-off was generally more hated than the rest, but Jake didn't pay any attention to that. It's unique storyline and captivating characters (especially a certain blue-haired girl he secretly admitted looked cute) hooked the teen into liking the series more than any other.

"...What was I doing again?", asked Jake before he remembered. Oh yeah, he had to finish unloading all the boxes. He immediately left to stand up and turn towards the exit before he suddenly dropped the pack of cards by accident. The pack itself burst open and spread the various Duel Monsters cards along the floor, leaving behind a huge mess to pick up.

"Shoot", Jake chastised himself as he crouched to pick up the cards from the carpeted gray floor. "Gotta be more careful next time."

However, a particular card began glowing with mysterious power, alerting the teen to his senses. Despite the possible danger, Jake steeled his resolve and picked up the glowing card.

"...Rank-Up-Magic Barian's Force?", read out loud Jake in bewilderment before remembering something particular about the card. Wait, wasn't this card a powerful card in the ZEXAL anime?

Before he could think any more, though, the spell card glowed in a bright light before shooting out various green streams, all enshrouding the alarmed teen.

"WHAT THE-", Jake never got to finish his sentence as he was suddenly blinded by a bright light once more, erasing his recent memories as the green streams finished entering him. When all was said and done, the teen suddenly jerked backwards, colliding with the floor with a thump and losing consciousness.

...

"...What just happened?", silently asked Jake himself as he stood up to survey the area. Where was he? Oh yeah, in his new room. He was picking up several YuGiOh cards, if he remembered correctly. Wait, didn't one of the cards-

Jake stopped his train of thought as a shiver suddenly coursed through his entire body, all his body hair falling off to leave behind impossibly smooth, creamy skin, sensitive against the teen's baggy clothes.

As the teen shivered, the last memories of having body hair and a glowing magic card were erased from Jake's mind, leaving him with only the memories from before then.

The changes were now starting to take place.

"...What the fuck just happened?", said Jake to himself, standing up slowly to continue unloading the boxes. Did he just collapse from exhaustion? Jesus, he needed to sleep more. The teen admitted that he avoided sleeping now and then to work on his new job, but he had no idea that moving into a new house took a toll on him that badly.

As the teen continued to move the boxes, though, the green streams inside his body continued to do their busy work. Jake decided to put on some earphones and play some music to distract himself, not noticing how his spine cracked until he shrank down a few sizes, settling into a new perfect height. He didn't notice the height difference as he picked up another cardboard box, either.

What I'm confused about right now is how tired I felt, mused Jake as he left another box in his room. This is the first time I-ooooooooooh~

Jake suddenly moaned as his body continued to change, destroying his Adam's apple and raising his voice by a few octaves, leaving behind a perfectly girly voice. The teen then collapsed on the floor, not noticing how his facial features began modifying themselves. His eyes grew into a cute size, with fluttery, lengthy eyelashes to accompany his new, red crimson eyes. His annoyingly flat lips increased in volume until they became soft, plump kissable pillows. His nose then shrank down into a small petite size, while his face and cheekbones cracked until it left a new shape, perfect for the new person he was becoming.

His memories of collapsing and moaning were suddenly erased too, having left just as fast as they arrived.

Jake stood up once more, this time convinced that something was happening. But he couldn't place a finger on what it was. Any suspicion was quickly erased from his mind thanks to the green streams.

"...Just what could be the cause of this?", Jake scratched his hair as he began thinking, not noticing how his hair began to lengthen as a result. His blond hair began changing into a baby blue color as it dropped down the sides of his face, while dark streaks of sapphire accompanied soon after. His hair dropped down until it reached just below his blocky shoulders, which desperately needed some fixing~

As Jake continued thinking, his shoulders cracked down with a large pop into a cute, new shape, his hips also suddenly expanding into a new childbearing size. The teen had to slow down as he suddenly felt off, before beginning to walk in a new way, swaying his large hips from side to side instead of the usual. He couldn't place a finger on it, but he felt more comfortable walking this way.

I feel much more better walking like this, the teen thought . I feel much more cuter like this~

Jake failed to notice how his train of thought changed trajectory, while his body continued to change from the green streams' work. His large hands shrank down until it reached a dainty size, his fingers also shrinking down into perfect girly proportions to boot. His arms soon followed, all the unnecessary fat and muscle receding into his body as they shrank down into acceptable sizes, now leaving behind small, petite arms perfectly normal for a teenage girl.

His central body was next, the teen ignoring how strangely sensitive his body began to feel. His stomach receded into his body as it left behind a cute tummy, his privates beginning to harden without him noticing. Lastly, his back arched down to leave behind a perfect arc that any girl would kill for.

Jake continued listening to his music as he failed to notice how all the unnecessary fat was pushed down into his annoyingly masculine legs. His legs were soon fixed into a new size appropriate for a girl, though, as his thighs began to lose unnecessary muscle and instead gained soft feminine fat. His feet also shrank down into an acceptable size, Jake almost tripping by the sudden changes.

The teen had to take a breather and try and assess what was going on, failing to do so as he began moaning in delight again. His erect dick was as hard as ever, the teen only being able to express delightful confusion at what was happening.

I swear something is happening to m-EEEEEEEEEE!~

The teen had to hug himself as he dropped to his knees, his body suddenly feeling strange as the streams changed direction. All the remaining fat in his legs began to move towards his ass, slowly increasing in size until it suddenly bloated into a large but soft, jiggly bubble butt. It's new size made it so that it strained against his stretched underwear and pants.

The teen then stood up, only to almost fall backwards from the new center of balance thanks to his new, large ass. As he stood up again to find his new center, his memories continued to be erased as his brain began to modify itself into someone else's, replacing memories and moments of his childhood with newer ones, ones that belonged to a certain blue-haired girl.

Jake then continued moving the boxes, now struggling to do so as his strength was already lower than before. He didn't seem to mind, though, as he thought that a girl like him didn't need strength. He continued carrying another box into his room, this time swaying his large, bubbly ass side to side in an attractive manner without him noticing.

As he left yet another box at his room once more, Jake couldn't help but feel a tugging, freezing sensation in his head, raising one of his dainty hands to touch his now-different forehead. As he thought, he was feeling unusually cold, yet he did not felt any sickness at all. Was there something wrong with him?

He could not find the answer to that, as he was suddenly distracted by how his thighs expanded into soft pillows, crushing his manly privates in a delightful manner. His already-erect dick was growing even bigger, almost to an impossible size. Jake moaned in a high-pitched, girly voice as a shock of pleasure jolted through his body.

This time, the changes that were happening were too major to ignore, Jake now noticing how his body has greatly changed.

"What the fuck is happening to me!?", the teen asked himself as he took off his earphones, only to then notice his small hands as he did so. "H-huh!? These are a girl's hands, w-why do I-oooooooooh~"

The teen could not finish his sentence as he suddenly began cumming, the green streams pushing out all the unnecessary testosterone through his erect privates. The sperm in question disappeared as soon as it came out, slowly but surely shirking the teen's dick.

Jack was left in a state of confused delight as he became nothing more than a moaning and blubbering mess, using all his energy to stand up and run to the bathroom. His large, swaying hips only made it harder for him to run, making him hit the wall with a large thump. Despite hitting the wall, though, the teen's body felt pleasure instead of pain, making the confused teen yelp in ecstasy.

Jake ignored his aroused thoughts as he eventually managed to enter the bathroom, just barely grabbing the marble bathroom counter. The confused teen then spent a few moments recollecting himself, refraining from moaning and squirming any further. He also spread his large legs to prevent his dick from being squished by his now-thick thighs~

Jake then looked at the bathroom mirror in front of him to see that he has changed. Greatly changed.

In front of him was a cute, blue-haired girl with alluring red eyes and plump lips.

Wait, what?

Jake immediately recognized who he was looking at. Rio Kastle, anime girl from YuGiOh ZEXAL, and one of his favorite characters. Yeah, the blue hair and face seemed to match up, but why? And, most importantly, how did he suddenly turn into her?

"...No way this is me", began to speak up Jake, only to suddenly cover his mouth from the new feminine voice coming out of it,finally hearing his new voice with clarity. He really was like her. Not a single visible trace was left of the old him. Well, at least his chest was still the same.

Of course, he felt that it would not remain so for long.

The confused teen suddenly felt another wave of pleasure course through his body, the green streams gathering all the useless fat left and depositing it behind his sensitive nipples. As Jake continued squirming in pleasure, the fat behind his nipples began to increase more and more, going past A and B cups to then stop at a C cup. Jake stopped himself from moaning once again as he then saw what was building up in his chest.

"Huh!? N-no way I'm actually growing b-b-boobs-AHHHHHHHHHH~"

The remaining pleasure in his body skyrocketed as his new breasts exploded in size, growing into immense DDs that heavily strained against his shirt. The confused teen then lost consciousness once more as he landed against his new assets and on the floor.

...

"Ughhh... what just happened?", stood up the dazed teen, trying to recollect what happened to him. Strangely enough, he remembered how he dreamed about how he was transformed into Rio Kastle from YuGiOh ZEXAL.

However, as soon as he saw his reflection in the mirror, he saw that it was no dream.

A cute, blue-haired girl was staring at him back, spotting a blushing face of confusion.

But something else was off. His mind has changed way too much to the point where the teen didn't feel panic anymore. Instead, he felt anticipation to explore his new body.

Jake slowly and silently began to take off his shirt, pulling it over his ruffled hair to reveal his new breasts underneath. He felt an ounce of hesitation as he reached to grab his right boob. He resolved himself, though, and began groping his new assets, silently moaning as he felt a new wave of pleasure spike through his sensitive body.

"Mmmmmm~", moaned the teen in delight as he continued groping his breasts. "They're so big and soft..."

It soon became addicting to the aroused teen, as his new mounds felt like soft and squishy pillows. They were heavy too, but that just added to the newfound ecstasy. "W-wow! It feels so gooooood!~"

He then came across his erect nipple and squeezed it, earning a high-pitched yelp from the blue-haired teen. He almost fell down towards the floor, only to grab the bathroom counter again to balance himself.

"My nipples are much more.. s-sensitive than before", noted the teen as he stood up. "So this is what having boobs feels like..."

He then moved his blue hair to the side to see his face clearer as he said, "Well don't I look cute~", while studying his new facial features. He then pursed his lips while playfully winking, giggling at how cute he had become.

"Even my giggles sound amazing!"

After a while, Jake decided to leave the bathroom to go to his room shirtless. While walking, he couldn't help but notice how his bubbly butt was swaying from side to side.

"It feels so goddamn good down there~", giggled the blue-haired teen to himself, reaching to grab his new fat ass as he continued walking. "And even my hips are bigger too~"

The teen eventually entered his room, grabbing a full length mirror from one of the large cardboard boxes and placing it against the wall.

After staring at his upper body, the blue-haired teen slowly took off his pants and boxers to reveal his bottom. Besides the out-of-place manly privates, everything else was like a body any other girl would have. Small feet, slender legs, wide hips, and of course-

"I sure have a fat ass~", winked the teen as he groped his behind. He then sexily bit his plump lips with lidded eyelids before laughing at how stupid he looked while doing so. He couldn't help but secretly admit how turned on he was by that, though.

Jake snapped out of his horny thoughts when he noted, "...But Rio doesn't have a body like this. Is this how she would look like if she was grown up?". If he remembered correctly, Rio was still a preteen back in ZEXAL. His new body looked more or less like Rio if she was an adult teenager.

However, Jake was pulled out of his musings when he suddenly yelped in pleasure, as the last change in his body took place. He jerked backwards and landed on his bed as he hugged his stomach, his dick beginning to shoot out the last of his testosterone and male sperm. It then shrank and shrank until it transformed itself into a small nub, his balls receding and folding themselves to create a slit. With this, Jake, no-Rio, was completely a girl now. The teen lost consciousness one last time as she fell to the bed, the green streams leaving her body and going back into the 'Rank-Up-Magic Barian's Force' card, almost as if seemingly completing its purpose.

...

"Nnnnnnhh...", groaned Rio as she woke up, only to cover herself with her bedsheets when she realized she was naked. What was she just doing?

Don't tell me I masturbated while I was naked, thought the blue-haired girl as she covered her face in embarrassment. A knock on the door jolted her to her senses, however, as she heard who it was on the other side.

"Oi, Rio, wake up and get dressed!", spoke up a masculine voice. "Today's my rematch duel with Yuma, and I don't want to leave you alone here!"

Rio mentally facepalmed herself at how obsessed her brother was with surpassing Yuma and proving how better he was. But well, that was her brother for you.

...Wait, her brother?

Oh yeah, she had a brother. More specifically, Reginald "Shark" Castle, one of the best duelists in Heartland City and Barian emperor.

The last of Rio's memories were instilled inside the blue-haired girl, every trace of Jake already erased from existence. The naked girl present was now 100% Rio.

"Yeah yeah, I'm coming!", said Rio as she stood up to get dressed. Well whatever, at least she knew she wasn't going to be bored today.

As the blue-haired girl absentmindedly put on her knee-high stockings, she did not once think that the room she was in wasn't hers. It had been a few days since both her and Shark moved here, especially since the Fusion Dimension's Duel Academy attack destroyed their old manor. Their new house was no mansion, but at least it was cozy.

Ever since the Ancient Gear attack, Heartland City has been in a constant repair mode, and with added assistance from Duel Academy as some sort of apology, the only thing left to take care of was some sort of entertainment.

And what better entertainment than Duel Monsters!

The blue-haired girl then put on her panties and pink lace bra, before noticing how huge her breasts have grown, straining against her tight underwear. Damn, puberty hit her like a truck.

Her thoughts have only been confirmed as she put on her pink shirt, her large mounds also sticking out noticeably against her top.

"Ugh", covered Rio her face while beginning to ponder to herself. "I'm going to need to shop for some more clothes tomorrow". Her face then lit up as she thought, "Maybe I can go with Tori, she seems the best to know what type of clothes fit me best."

She proceeded to put on her skirt (which just barely covered her ass) and jacket before she saw herself at the mirror. Huh, besides the obvious problem of her clothes feeling tighter than usual, she still looked decent enough to go outside.

Suddenly, she felt a growing sensation down there, only to realize that her pussy was aching with want. The girl also saw that her nipples began to stick out through her shirt.

No way she was getting horny over wearing tight clothes. Goddamnit.

Well, better die on this hill, then.

"Mmmmmph~", Rio silently moaned as she began caressing her creamy thighs, noticing how plump they have grown alongside her bosom.

"Even my thick thighs feel aroused by being so big~"

The blue-haired girl began feeling herself up as she felt her body grow more sensitive, groping her large, jiggly ass with passionate fervor before moving to her large breasts. Wow, she really did get a glow-up on all the right places~

She placed one hand on her right boob and the other down her snatch as she began paying attention to her sensitive areas.

Ahhhhhhhhhhhh~ ...My huge boobs and ass feel so goood~

The teen slowly caressed her soft breast with attention, slowly picking up the pace while rubbing her clitoris. After a few moments of grabbing large handfuls of soft fat, the girl pinched her right erect nipple, earning herself a loud moan of arousal.

"AHHHHHHHHH!~"

"Rio, are you okay up there?", shouted Shark from the first floor, already set to leave.

The girl in question panicked back to her senses and answered, "Y-yes, I'm fine! I just tripped on something and was about to fall!"

"Be more careful, dammit!", stated his brother while trying to hide his worry. "You're scaring me for no reason!"

The younger sister rolled her eyes as she suddenly felt like she didn't want to continue touching herself. She changed panties (the one she wore right now were damp) and put on her shoes, already proceeding to turn to the room's exit and leave. However, she felt like she was missing something.

She then turned to see her Duel Monsters deck. Why, of course, she was about to leave her Ice Deck behind! The blue-haired girl picked up her Deck to study her precious cards, each one having their own fond memories and moments.

And then there was Rank-Up-Magic Barian's Force.

The card brought up a lot of bad memories to the girl, back to the times where was forced to fight against her dear friends. She still shivered once in a while at the memory of being absorbed by Vector, after she lost against him and Don Thousand, too.

But the teen steeled herself up. The only way to make up for her past and wrongdoings was to move on, and what better way than to start now.

Rio was pulled out of her musings when she suddenly felt her right bra strap snap and tear itself off, making the girl yelp in surprise.

Jesus, she really needed some new clothes.