Rin and the Book of Cows (Fate Bimbo Cowgirl TF) (Patreon)

Hey folks. If you missed the announcement, I've been forced by illness to delay getting back to my regular schedule for another month. Billing has been paused for May in accordance.

Being sick is incredibly annoying. I don't really have much more news this week than that, so enjoy the apology short!

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Rin Tohsaka was the idol of Homurahara Academy, and it wasn’t even close. She was perfect in every conceivable way (unless you asked the student council president), and she made no secret of the fact. She was smart, with the highest grades in the school, beautiful, with numerous boys and girls falling over themselves to compete for her attention, and, above all, eternally distant and reserved. Oh, she wasn’t a jerk, or mean, or anything like that – she was always the picture of politeness to acquaintances, and a dependable support for her friends. But there was always an aura of mystery about her, a mystique that no one else could penetrate. An idol, after all, should be like an ever-distant utopia – something beautiful that would always remain just out of reach.

All of this was deliberate on her part, of course. Her public image was a careful construct that she had meticulously designed and executed without pause and without fail over the course of her growth into adulthood. And now that she was an adult, the guise of Rin Tohsaka, prim and proper student, was so strong that, quite frankly, she could roam the school halls naked while blaring punk music from a loudspeaker radio and not one person in the school would blink or change their opinion of her. They’d just decide that they must have been imagining things, and go back to their day, all memory of the discrepancy erased from their minds. It wouldn’t even take magic to do it.

Though magic was an option, because in truth, Rin Tohsaka was a magus – a graceful and elegant one when she was on her game, or a grouchy and short tempered one when she wasn’t. The rough edges to her personality that no student of Homurahara could ever acknowledge were certainly there, and they played a few more important role in her hidden life than any normal person could ever dream…

… But right now, none of that mattered. Because right now, Rin wasn’t busy with her preparations for the Grail War (It had already gone past, after all, and wow, wasn’t that a story!), or plotting out magus schemes (She’d left all those simmering at home). No, right now, Rin was just a simple school idol, doing her simple duty as a student and helping out at the school library by organising the books on the shelves. An easy task for someone of her incredible capabilities, though she was diligent about it none the less. Honestly, pretending to be a normal student was one of the most relaxing activities she got to do as a mage, and she was all too aware it wouldn’t be available to her for much longer, so she was enjoying it while she had it.

So, here she was, just going through the shelves, making sure everything was in order, and… Oh, huh. That was strange. Her finger, running along book spines as she travelled down the aisle, snagged, and she paused. The book she’d stopped on was… unusual. Most of the books in this section were rather new, with clean plastic covers and clear titles, but this one looked more like the kind of book she’d find at home, in her secret archive of magical tomes. It had a thick, leather bound cover, and stood out from its companions on the shelf like an elephant in a sheep pen. Odd, why hadn’t she noticed this one before?

Getting it down to examine it didn’t shed light on anything. The book had no title on either its spine or its face, and the pages within offered no clues, seemingly written in a language that even she didn’t recognise (and she recognised most). It was certainly an odd find for a school library, that was for sure.

Well, whatever. It definitely didn’t belong here, whatever it was. With a shrug, she turned around to head back to the librarian’s counter and hand it in – they might recognise it, and if not, they could throw it out. There was no reason to make this her problem, after all.

But before she could even take two steps…

“Oof! Hey, watch where you’re going, you stupid cow!” The school idol was bounced violently to one side as someone crashed into her shoulder, sending her crashing into one of the shelves she had been walking past, and sending the book she’d been carrying to the floor. Quickly, she grabbed the unit, making sure it didn’t fall, before her mind clocked on to what had just been said.

“Excuse me?!” She spun on her heel, her glare already set to stun and climbing up to kill. “Who do you think you’re talking to, you-”

But whoever had run into her (and they’d definitely run into her, thank you very much) had already vanished, stalking off between the aisles before Rin could get a good look at them. The magus twitched, before forcing herself to regain control of herself. She couldn’t allow herself to show her temper here at school. No, if she wanted to teach that jerk a lesson, she’d have to be much more cunning about it.

Hey, maybe that was petty, but her shoulder really hurt, y’know! Hmph.

No, no, never mind. It wasn’t worth actually getting mad over. Rin sighed and rolled her eyes, before looking down to find the book she’d dropped. Where had it gotten too… Huh?

The mage blinked as she spotted her missing tome. There it was, lying on the ground at her feet. But… Was it just her, or was the book… glowing? Strange golden light seemed to be leaking out of its pages, trying to claw around the closed cover. A cover that now had a title…

Now, Rin was not a fool. She had a sharp mind, even for a mage, and she knew very well that one had to act carefully around an unknown but potentially magical item, even if it was just a book. In fact, she knew that some of the most dangerous magical items out there were books! But when the potentially ready to explode bomb is lying at your feet, in the middle of a public library, you don’t really have as many options as you’d like to deal with it. So, brow furrowing, but otherwise looking unconcerned, the mage cautiously leaned down and picked the tome up, her eyes taking in the new title engraved upon its face.

‘Stupid Cows Change Book’

… An odd title, to be sure. Hm, had it just taken the words that had been spoken at it? That didn’t seem so bad. She wasn’t sure how such a book had gotten onto the shelves at her school library (maybe another mage had left it here by accident? She could think of a few who might have done so) but as long as it was that harmless then she didn’t need to panic. Breathing a sigh of relief, she opened the book up once again to check the pages within, just in case they had changed as well.

They had – or, rather, they were. As she opened up the first page, she could see the strange characters, the ones she’d been unable to read, swimming over the pages, forming themselves into legible, recognisable letters. Still frowning, she waited for them to spell something out, unable to deny her curiosity for what it said…

“Bimbo!”

“Huh?” Rin blinked and looked up. She thought she’d heard someone just then – someone insulting her? But there wasn’t anyone around. Confused, she looked back down at the book – only to realise that the word Bimbo was the first one to take shape on the page.

Her eyes narrowed, and she peered up and down the library aisle again, just in case, but the hall remained empty. She really was the only one here. Had she somehow read the word and mistakenly thought she’d heard it said aloud, or was it some kind of magical effect? Ngh, this kind of situation made her head hurt… She looked back to the book, hoping to get some answers.

“Tits for brains!”

Only to jump and look around as another yell startled her. S-surely she hadn’t imagined that! It had been really loud! But once again there was no one there. Ugh, this was really weird…

Rin shook her head and went back to reading – failing to notice the new blonde colour slowly making its way up from the tips of her twintails. Or, for that matter, how tight her red top was starting to get around the chest region. Nothing to worry about, surely – not when she had a strange book to work out.

Just like before, the mage found herself frowning, as she saw that Tits for brains was now written on the page in front of her clear as day, just under Bimbo. H-huh. This was getting, y’know, super strange. Something, like, totally weird was definitely going on here! Good thing she was a super smart mage ready to work it all out! What else was written in this book? Uh, the next line was…

“Horny Cowgirl!”

“Huh?” Unlike before, when Rin had been both surprised and offended at the sudden insult yelled in her ear, this time the magus was just surprised and confused, taking a few seconds to work out what she’d just heard. Horny… Cowgirl? Why would someone call her that? She wasn’t that horny!

… Ooohh… Um. M-maybe she was, actually. There was a sudden heat rising between her legs, and without a thought she found herself squirming, her thighs rubbing together underneath her short black skirt. For some reason she actually was feeling really, ah, really hot right now…

A small blush coloured the genius mage’s cheeks as her breath grew heavy, and she fought to keep her hands out of her panties. No no, she, like, couldn’t do that here! People’d see, silly! The mostly blonde girl – her former dark colouration now little more than dirty roots beneath a sea of platinum - giggled and shook her head. She could have fun later – first she had to figure out what was up with this neat book!

Besides, even if she was, like, super horny, she definitely wasn’t a cowgirl! That was just dumb, y’know? Like, cows made milk n’ stuff – she had no idea how to do anything like that.

Still unnoticed, naturally, her red top, already stretched, strained to almost breaking point as the chest beneath it swelled out another cupszie, and developed a pair of dark, wet splotches at just around the height where her nipples would be…

So, what had she been doing? Oh yeah! She was reading! Although this book was, like, super hard to read and stuff. The way the words were moving around on the page in front of her was almost like a pattern, actually. Like this big, swirly spiral, spinning around and around before her eyes… And in the center of it all, another phrase beginning to form…

“Dumb Slut!”

The mostly-blonde mage tittered vapidly, a small grin widening into a stupid smile as a black spiral began to curl out from the edge of her irises, swirling through her eyes at a building speed. Unthinkingly, the hand that wasn’t holding the book now slipped down under her skirt and started to massage her lower lips, but her gaze never wavered from the page as more words continued to form.

“Bimbo boobs!”

“Oooohhh…” Rin moaned, her eyes fluttering and almost rolling up in her head as her hair finished turning a complete platinum blonde, and her brains continued shrinking. Her no longer needed intelligence was now flowing down into her chest like an open faucet into a water balloon, pumping her breasts up bigger and bigger, this newest expansion finally pumping her up large enough for her top to rip completely open! Useless red fabric fell to the floor, completely forgotten, as her now proud bimbo boobs bounced and jiggled freely in the air.

And still she continued to read, the spirals in her eyes now completely consuming even her pupils…

“Cow brain!”

“Horny Heifer!”

“Moo moo moron!”

“Ah! Ahhh! Muh… Muh-aahh!” The words all hammered into the mage’s small and soft brain, becoming utterly true as they transformed her body and mind alike. Her clothes vanished, evaporating into thin air as they were replaced by a black collar and a golden cowbell resting against her cleavage. Her breasts grew, and grew, and grew larger still, greedily draining every last drop of intellect from her emptying head. Small horns poked up through her shimmering golden hair, and spirals pulsed, complete and pure, having utterly dominated her eyes…

Until finally, one last insult pushed her over the edge.

“Milk for brains!”

“Muh- Muh- MMMMMMOOOOOOOOOO!!!!” Pleasure exploded through the woman’s body as her mind, everything that was left of Rin Tohsaka, school idol and elegant magus, utterly and completely melted into milk, drizzling down into her tits and finally bursting out of her, spraying all over the library floor in a thick stream of white creamy goodness, accompanied by a clarion cry as she accepted her place as a dumb, horny bimbo cow.

Then as the milk dripped from the shelves, the cowgirl kneeling in a white puddle of her own former genius with a wide smile and spiralling, vapid eyes, the world around her went dark. The library vanished. That didn’t concern her, of course – all this dumb little cow cared about was getting milked.

And, to her delight, out of the shadows snaked two mechanical looking breast pumps, each one latching on to her still drizzling nipples, and starting to suck. The cow couldn’t help but let out another blissful “Mooooo~” as her wonderful milk was steadily pumped out of her, down long hoses leading off into the darkness. Where it was going, or who had brought her here? She didn’t care. She was being milked – and that was all that mattered.

…

Back in the library, there was no trace of Rin Tohsaka. Just a strange puddle of milk in an empty aisle – and in the middle of it, a mysterious looking tome. It was an odd one for a school library – old, leather bound. But strangest all was the title, ‘Stupid Cows Change Book: Rin Tohsaka’, written in gold on the spine and on the cover – and beneath it, the image of a dumb looking blonde cowgirl with blonde hair and massive tits, smiling happily as she was pumped away…

A hand reached down and plucked the book from its puddle, shaking off a few of the drips. Then, silently, it was carried away- away from the library, from the school, from even the city that Rin had known so well (before her brains turned to milk, at least). Until at long last, in a place very far away, the book was placed on a shelf of its own – next to a dozen other, similar tones, all with names quite like this one, and covers equally interesting women in equally interesting positions…

A shelf with more space yet left to fill…