Title: Boy and girl?

Fandom: Prince of Tennis

Pairing: Atobe Keigo/Tezuka Kunimitsu, one-sided Oshitari Yuushi + Sanada Genichirou

Rating: T (PG13~R)

Genre: AU, romance, comedy

Warnings: gender-bent boys who refuse to act like girls, general craziness, some talk of sex

Summary: Oshitari Yuushi finds himself in many situations he really would have preferred to avoid. Somehow, he doesn't suppose many of them will end as well as he wishes they would...

Disclaimer: I own nothing under the name of The Prince of Tennis. The characters belong to their creators (manga author Konomi Takeshi, the studio that made the anime). I write the story for fun, I make no profit from this.


The room was dimly lit. Layers of dust covered every surface but one desk, littered with various ingredients of unknown origins. That one desk was also the only place in the room that carried any signs of being used; pages and pages of complicated alchemical formulas, small bowls and lots of pens lay on one side in disarray, while the other side was strangely tidy.

There, on a special stand, stood multiple vials filled with liquids, arranged by the intensity of colour. At the back were the neon pink and almost purple ones, while the pastel, light pinks sat in the front. Many in-between hues could be found in the middle rows. Each vial seemed to catch light in a slightly threatening way. The liquids seemed to bubble dangerously.

Next to the desk was a chair. On that chair, tied tightly and unable to escape, sat Oshitari Yuushi, wondering what sin he'd committed against humanity in general and Atobe specifically to have found himself in such a situation. The last thing he remembered before waking up in this highly uncomfortable position was... Ah, yes. Studying. He helped tutor Tezuka for another Latin test, he had tea and all of a sudden, he was very sleepy. There had to have been something in the tea.

Atobe, the sly bastard. Oshitari should have known better than to trust him.

Still. Where was this abandoned place? The room was big enough to fit thirty people for a dance class, and it held lots of equipment Oshitari probably couldn't even name. It was safe to assume it was some kind of a chemical laboratory, albeit a rather neglected one. Somebody had to have been working there, though, judging by the one tidier desk.

What was the purpose of bringing him there? Oshitari had to wonder. Was it a punishment Atobe inflicted upon him for something or another? It seemed probable, although he couldn't imagine why the pompous heir would take such troublesome means in order to discipline him, when he could have just as well stopped talking to him.

Well, regardless of what intent of Atobe's had brought him there, Oshitari didn't want to stay in the dark laboratory forever. Actually, he wanted to leave as soon as possible. Something was definitely not right here – besides the fact that he was tied up and unable to move. He tried to free his hands, but the bonds were too tight. It actually hurt.

'I'm sorry, Oshitari-kun,' said a soft voice from behind him; a vaguely familiar voice at that, one that made him shiver in anxiety. Something akin to fear started to creep up Oshitari's spine. He wished he could look behind him, but at the same time, he was thankful that it was impossible. This way, he could postpone the inevitable horror of recognizing his captor for a few seconds more.

A guinea pig squealed in the corner, recognizing its master and demanding attention. From the sound of it, the animal wasn't agitated in the least, which was somewhat interesting in a chemical laboratory, where its kin were usually put at high risk. Oshitari wondered whether it was a good omen or a bad one for him. Many psychopaths were animal lovers. Most of them weren't that fond of humans.

'I assure you, I am not going to hurt you, Oshitari-kun,' promised the same soft voice and the genius of Hyoutei could hear the cluttering of a cage being opened, as well as the sound of food being poured into the animal's bowl. At least, he supposed that's what it was. 'Atobe-san made it perfectly clear that he doesn't want to collect your corpse. I assured him that the probability of you dying during this experiment is less than fifteen per cent. He was quite content with that, from what I gathered.'

Oshitari paled. Fifteen per cent. It was quite a lot, wasn't it? That Atobe. Of course he wouldn't really care if Oshitari was put at risk. He only cared about Tezuka. And tennis too, but mostly Tezuka. What kind of crazy punishment was this, and why did he have to suffer through it?

He didn't want to die.

His captor finally came closer to face him. Recognizing him, Oshitari didn't know if he should be relieved or horrified. I front of him stood Seigaku's Inui Sadaharu, wearing a white lab coat. He wasn't smiling and looked pretty tired. All of a sudden, everything made sense.

'I'm your human guinea pig,' the genius of Hyoutei said.

'Yes, I'm afraid so. Atobe-san volunteered you, since at this phase of the experiment, the influence of the juice on humans has to be tested,' replied Inui politely. 'Let me explain to you the procedure.

'First of all, you are to be referred to as Specimen Y from now onwards. This is a normal course of action to simplify the protocols. In each stage of the experiment, the specimen's overall condition will be closely monitored to avoid any risk. The procedures are simple: each stage of the experiment is divided into three phases. They all begin with serving the specimen a potion from a suitably tagged vial. Following this, a protocol will be prepared, in which each reaction of the specimen will be properly marked. The last phase is a thorough examination of the specimen to search for the desired effects.'

'Great,' said Oshitari, voice dripping with heavy sarcasm. 'And out of sheer curiosity: how many stages of this have you planned?'

'As many as are required to achieve the goal,' Inui said vaguely, ignoring the sarcasm. 'However, there is a probability of eighty-two per cent that only one trial will be needed.'

He turned to the desk and procured a pair of synthetic gloves. With a somewhat manic smile, he slipped them on and said,

'Shall we proceed?'


Oshitari opened his eyes after what felt like hours of sleep, filled with dreams and shadows he couldn't remember upon awakening. He frowned and shook his head, which caused his glasses to slide down his face, where they sat in a crooked way. This served only to irritate him slightly, but he said nothing, instead glaring at Inui, who stood in front of him with a rather satisfied expression on his face.

'The experiment ended successfully,' said the dataman. 'Please wait here, Oshitari-kun, while I contact Atobe-san.'

'In case you didn't notice, I'm tied up and can't go anywhere even...' Oshitari began, but didn't finish. His voice. Something was very, very, very wrong with his voice. 'I'm... I'm a girl,' he realized, blinking as he looked down at his body with wide eyes.

The first thing he noticed (apart from the glasses, which were bigger than they used to be and fell down to his lap; luckily, they were only for show and their lack didn't affect his vision in the slightest) was the bust. His breasts were enormous, enough so to make the shirt of his school uniform fit tightly to his chest. While Tezuka was pretty flat, which was actually normal for a fourteen years old girl, Oshitari was easily a size FF. He shot a dark look at Inui, suppressing the urge to call him a pervert, since he was technically still at his mercy. He didn't want the dataman to get any weird ideas. Definitely.

He just wanted to go home, actually. He felt very tired, strangely so, considering that he had been sleeping for some time before and had done no physical exercise for who knew how long.

Inui disappeared somewhere, presumably to call Atobe. Oshitari sighed and wondered what would happen to him next. He didn't look forward to being Inui's full-time human guinea pig, but on the other hand, he could not go back to Hyoutei like this. Shishido would laugh his ass off at him, and that was completely unacceptable. Moreover, it would probably be enough to blow Tezuka's cover. His team-mates were dense at times, but they were certainly not completely stupid. Two familiar-looking girls showing up while two boys went missing would surely give them enough of a clue to solve the puzzle.

He supposed he could just stay at Atobe's place, feigning sickness until Inui gave him an antidote, or something. The thought had a nice ring to it. In the mansion, he could always eat as much as he wanted, and there was that wonderful swimming pool to cool off in, oh, and the music room, where he could play the violin for as long as he wanted to. He wouldn't be missed at the tennis practice, because there was no such thing Hyoutei anymore, and he resigned from the club anyway; he was also bright enough to skip school for a couple of days, since he would be able to catch up with the rest of the class in no time at all.

Although he didn't expect Atobe to want him around all the time. Somehow, he was under the impression that the pompous heir didn't like him all that much. This latest incident of offering him as a lab rat for experiments was proof of that.

'Atobe-san said the driver will pick you up in ten minutes,' Inui informed him, reappearing in the room. He untied Oshitari, who got up, massaged his poor wrists, and stretched.

His muscles were sore, and the breasts were surprisingly heavy. He sighed; he needed a bra, and he needed it as soon as possible. He also needed clothing that would actually fit him, since he was close to losing his uniform pants, which were much too big for him now, even though his hips were nicely, proportionately wide. He wondered briefly if Atobe was going to buy anything for him to wear. He doubted it. Atobe never bought things for him out of kindness.


He was obviously wrong; some clothes were already waiting for him in a bedroom that Atobe told him was to belong to him for the time being.

'Of course, you will be living here. I have to keep you under surveillance now, Yuuko,' said the heir when Oshitari asked. 'You may rest now. I will take you shopping later in the evening.'

But rest wasn't something Oshitari could obtain that easily, it seemed. Just after Atobe left him alone in the bedroom (a very nice and big one, as expected of any guest room in Atobe's mansion), sitting on the bed, Tezuka sneaked inside, with curiosity written clearly on his face.

'Atobe said you're also a girl?...' He asked, and then his eyes widened as he saw the confirmation of Atobe's words very clearly. Then, to Oshitari's amusement and surprise, he blushed. 'They're huge,' he said so softly that Oshitari barely heard him, quickly looking away from what he was looking at.

Meaning, the boobs.

'Yeah. Uncomfortable,' Oshitari replied conversationally. 'If you ask me, I think your pal Inui is a pervert.'

Tezuka laughed a bit weakly, most probably still recovering from the shock of seeing Oshitari's big breasts, and sat next to the genius of Hyoutei on the bed. He was feeling much better, now that his period was over; but he took to wearing baggy clothing at home all the time, a habit Atobe didn't approve of, but could do nothing about. He was also keeping his hair in a low ponytail, because Atobe refused to let him have it cut. All in all, he seemed much more used to the temporary body now than he had been in the beginning.

Oshitari hoped he wouldn't have to get used to it at all. Thanks to his (albeit unwilling) participation in the experiment, Inui knew the ingredients to the concoction that caused all of this now; surely, he would be able to come up with an antidote very soon?

'So, now we're both girls,' said Tezuka with a small smile; Oshitari rather liked it when the Seigaku captain smiled, it was a pleasant view that not many people could brag to have seen. 'What do girls talk about?'

'How should I know? I've never been a girl before,' Oshitari replied, grinning. 'Those at school always talk about boys, and about Atobe... oh, and pop bands. Do you know any pop bands?'

Tezuka shook his head. 'Do you?'

'Sure. Gakuto loves them. I don't care that much, personally,' Oshitari shrugged. He preferred different types of music. Like classical music. And cheesy love songs. 'So... boys? Wanna talk about boys, Micchan?'

'If you want to, Yuuchan,' replied Tezuka. 'After all, we know a lot about boys, don't we? Seeing as we are boys, actually...'

'Aww, stop spoiling the fun,' Oshitari poked him on the cheek. Tezuka chuckled. 'Anyway, boys. Let me tell you one thing about them. They are devious creatures, boys are. All they want from girls is sex, and some more sex...'

'Oh no. No way, Oshitari. I'm not discussing sex with you,' Tezuka protested, blushing and frowning at the same time. It looked indescribably cute, especially so since it was Tezuka, of all people, doing it.

'Okay. No sex. It's not like we can discuss much. I haven't had sex with anyone yet. You?' Asked Oshitari, rising his eyebrow suggestively.

'No! Of course I haven't!' Hissed Tezuka and hit him on the arm. 'Change the subject, or I'll tell Atobe you molested me!' He threatened in a low voice.

Oshitari laughed and lay down comfortably, closing his eyes. He wanted to loosen the buttons of his shirt a little, since it was constricting, but he didn't suppose Tezuka would appreciate the view it would undoubtedly present. That would be molestation for sure. He sighed.

'I think Atobe doesn't like me much,' he confessed, half-jokingly, although there must have been at least a hint of serious hurt in his voice that he didn't manage to contain.

'That's not true,' replied Tezuka, settling down next to him. 'Sometimes when he talks about you, it is clear that he holds you in high regards. I may not know him too well, but I can tell that he values your friendship a lot. I wouldn't expect him to admit it, though, he's not the type to reveal his real feeling that easily. He just keeps it all inside and takes care of you guys...'

'... You observe him a lot, don't you, Tezuka?' Oshitari inquired, cracking one eyelid open to glance at the other boy, who blushed and poked him between the ribs. 'Ouch! What was that for?'

'For stupid assumptions.'

Oshitari couldn't lie that he had no idea what assumptions Tezuka was talking about, since he had a fairly good idea concerning the matter. It may not have been clear to either of them, but Oshitari, as an outsider, could see how the two boys were attracted to each other. Of course, it had been the case with Atobe from the start and only a fool could miss it; Tezuka, however, didn't use to have this kind of feelings before the whole gender-swap fiasco, and this seemed to confuse him a lot. And any mention of the possibility turned him into an aggressive bully, as proven at that moment.

'Whatever, Micchan. You keep your feelings bottled up if you want. I can tell you about my crush, though. Since, you know, we're girls, and we should talk about our crushes, even if you refuse to admit to having one,' Oshitari said with a grin after a while of silence. 'You know that guy? Rikkai's Sanada Genichirou.'

'I've met him,' Tezuka admitted reluctantly, still glaring at the genius of Hyoutei as if he had done something really, really bad. Like kicking a puppy. Or a kitten. Something of this variety. 'He's your crush?...'

'Well,' Oshitari actually blushed a little, but went on without hesitation. 'Yeah. I've seen a few of his matches last year, and one this year... He's really passionate about tennis, isn't he?'

'I guess,' said Tezuka non-committally. 'I haven't seen him in a long time.'

Oshitari nodded. 'Well, I talked to him once or twice. Maybe talk is not the right word... more like, I was told off by him. Funny, he knew who I was. He charmingly called me a failure, or something to that effect. He said I was never going to achieve anything in tennis if I have no intention of getting serious about it any time soon. He also said that if I were in Rikkai, he wouldn't tolerate my laziness,' he laughed and shook his head. 'I just told him I was glad I wasn't in Rikkai, then, and left. But that night, I had my first wet dream of him slapping me and...'

'Oshitari, too much information!' Tezuka yelled and hit him with a pillow, hard.

The pillow fight that commenced then was epic, and the maids in Atobe's mansion would find feathers in many locations even months after the whole incident.


'I am not paying for that hideous thing, Oshitari,' hissed Atobe and the genius of Hyoutei pouted, but he hanged back the pink mini dress he was holding. It was already the third article of clothing that Atobe didn't like and refused to buy for him, and it was getting slightly frustrating. At this rate, completing a wardrobe for him would take months.

'I would wear it, though...' Said Oshitari, drawling the syllables like he always did, even though now, when his voice was changed, it didn't give off the impression of a purr that he wanted. It added to his irritation with life in general. 'Why do you have to be so difficult, na, Atobe?...'

'I will not have you dress like a common whore,' Atobe said with a tone of finality. He seemed completely immune to Oshitari's pout, even though the genius knew for sure it was super-adorable (he had practised it in front of the mirror for the whole of fifteen minutes, much to Tezuka's amusement; he had spent another quarter of an hour plucking the feathers from his hair). 'You shall wear proper clothes. You look indecent enough as it is,' the heir pretended he didn't cast a fairly disgusted glance at Oshitari's bosom.

'It's just tits, Atobe, girls usually have them. Even Tezuka has them, only smaller,' Oshitari pointed at the Seigaku captain, who was further back in the same shop, looking at the newest collection of fashionable menswear with unhidden longing. 'If anyone's to blame for mine, it has to be you, since you volunteered me for a sex change. And what the hell do you want me to wear, a sackcloth? Would that be proper enough for Your Highness?' He complained unreasonably; he was pretty tired after the pillow fight, and the events of the whole day prior to it.

'No, Oshitari,' Atobe said, exasperated. 'In fact, it would be enough if the clothes you chose covered as much as your underwear. Exhibiting it when you are supposed to make a good impression in your new school tomorrow...'

'What new school?' Oshitari interrupted him, blinking in surprise. 'You didn't tell me I was changing schools! Why should I?'

'Isn't it obvious, Yuushi?' Asked Atobe, rising his eyebrow in question. 'You are called a genius, aren't you? I hope you did not imagine you were going to continue attending classes the normal way while you are in this condition, because that would cause me to be disappointed in your supposedly superior intellect. Also, it is pretty much impossible for you to sit at home all day, I do not trust you enough to leave you all alone in my house for hours. Your idea of spending free time does not agree with my common sense, if you understand what I mean. Thus, I have some made arrangements, which were only possible thanks to an old acquaintance of mine – he is now hospitalized, but he still pulls all the necessary strings, which was rather convenient for my case.'

'Cut it out and say it to my face, Atobe. Where are you sending me?' Asked Oshitari, forcing himself to remain calm, even though he was rather worried.

Atobe smiled at him, and in that smile Oshitari could see his own nearing demise. The feeling of dread increased tenfold as the heir continued to smile in silence for the next few minutes, which felt like hours or days. Tezuka approached them with a jacket from the men's section (size XS, but as it was designed for men, it was still much too big for him in this form), giving Atobe a sweet, big-eyed look that was sure to win the hearts of everybody in the vicinity; the captain of Hyoutei nodded at him, and then turned back to Oshitari, who didn't even have the time to wonder when Tezuka had learned how to manipulate Atobe this effectively.

'As much as I hate to explain everything in such a wretched environment, I will do so upon your request. You certainly do remember that you said you would love to be a girl, since that would make Rikkai's Sanada fall head over heels for you,' he reminded the genius, and the smile on his face turned into an evil, evil smirk. 'Here comes your chance. Starting tomorrow, you will attend Rikkai Dai Fuzoku as Yukimura Yuumi, my dear friend Seiichi's cousin. I talked to him via phone and he promised to have the tennis club take care of you, which will give you a perfect opportunity to sweep Sanada off his feet,' he said, clearly amused. 'I will certainly be rooting for you. Be awed at my magnificent organizing skills!'

Oshitari somehow managed not to faint, but he still didn't remember how the remainder of the evening passed.


Going to bed late at night, he desperately wished the morning would never come. Or that he would wake up and it would all turn out to have been a dream, a scary nightmare. He hoped for it with all his might. He was even willing to give his pocket money to charity if his horrible fate of the following day could be somehow avoided.

Yet all his hopes and wishes were in vain. The morning still came, he was still a girl, and he was still going to Rikkai. He didn't suppose life could get much worse.

Oh, how wrong he was.