A Servant’s body is an odd thing.  Comprised entirely of Ether, their manifested form is more of a projection that forms around their Spirit Core, capable of being damaged and bleeding, but so long as the core of their being is undamaged, they will return to their initial state with sufficient amounts of Mana.  Additionally, while the form of a Servant is generally a representation of them at their prime during life, with few notable exceptions, they are largely unable to alter their bodies after manifesting without the aid of Magecraft or some sort of Shapeshifting skill.  And with bodies or pure Ether, a Servant needs only a constant supply of Mana to maintain their manifestation, though many do engage in consuming food either for comfort, pleasure, or curiosity.

Matter consumed in this way is completely converted into Mana and absorbed into the Servant’s body without any waste, and it is widely believed that a Servant need not worry about the nutritional value of their food because of this.  As such, the practice of eating a balanced diet is not necessary for a Servant’s health, however, within Chaldea, and by extension Novum Chaldea, because Servants are able to manifest for periods of time unheard of before, many have taken to ensure healthy meals are provided for all staff and Servants.

Due to the unprecedented circumstances of the Chaldean FATE summoning system, beings previously thought to be unsummonable by conventional means had also overturned many preconceived notions of what can and cannot affect a Servant’s body, Saint Graph, and Spirit Core.  From altering one’s Saint Graph to change one’s class to outside influence granting abilities and traits one never had before, much of what was understood about Servant physiology has been called into question.  And with the existence of Skills like Natural Body that clearly state that the possessor’s body will not change no matter how many calories they ingest, this has led many Servants to question if and how their bodies may store excess Mana gained from eating.

So, while no conclusive proof has been found to suggest a Servant can gain weight simply by eating, a predominant theory is that the subconscious image of oneself living an inactive, gluttonous lifestyle could lead to a slow shift in how one perceives themself, and thus gain excess weight.  Much like how a Servant can alter their clothing by envisioning the Ether covering their body in a different form.

As such, the mature, busty, beautiful librarian of the underground library, who normally would eschew such activities in favor of tending to her duties as head librarian, looked around nervously as she entered the women’s changing room adjacent to the fitness facilities.  Glancing at the bit of graffiti that had never fully faded under the sign forbidding men from entering which read ‘Except for Master’, she blushed as she pressed a hand into her belly and rushed to her locker.

With it being so late, there was, thankfully, nobody else in the changing room.  Opening her locker, she grabbed her water bottle as she shifted her clothing from her form-fitting gothic-style black dress and black-and-grey-checkered haori to the one-piece, black bathing suit she created for herself the previous summer.  Forgoing many of the decorative frills and accessories that she normally manifested with the revealing swimwear, it functioned more like a leotard for her to work out in.

Ahwawa…  My belly has been feeling softer lately.  I’ve been wearing my haori so Master doesn’t notice, but I can’t keep that up forever.  Sighing as the image of the handsome young Mage came to mind, she picked up a towel as she entered the gym, fully equipped with modern exercise machines, free weights, and a one-hundred-meter running track wrapping around the perimeter.  I let my guard down since summer, but snacks are a must when reading by such a beautiful lake-!?  Taking a few steps into the facility, she hadn’t noticed that there was, in fact, one other person there despite it being so late.  M-M-Master!?  What’s he doing here?  H-He should be in bed by now.  Because he was the one she most wanted to avoid, as well as a few other unsavory Servants prone to leering at her with lustful eyes that should be barrels deep in alcohol by now, she had specifically a time after he normally retired for the day.  Ahwawa.  I need to leave before…

“Hmm?  Oh, Murasaki-sensei!  I didn’t expect to see you here.”  Noticing the tall, fair-skinned Caster before she could run away, the dark-haired young man called out to her.  “What brings you here so late?  If you’re going for a swim, the pool’s over there.”  He said, motioning to a door on the far side of the room.

“Ah, Master…  I-I could ask you the same thing.  Did Scheherazade-sama not visit you tonight to read you a story?  I cannot imagine someone staying awake through one of her tales if she does not wish for you to do so.”  She said, blushing as he approached her and tried to cover her chest self-consciously.

Doing his best not to ogle her, Ritsuka glanced away from the eye-catchingly huge bust she had been blessed with, feeling his cheeks warm as blood flooded them.  “Ahaha… I… I just couldn’t get to sleep.  I thought coming to work off some of my excess energy would help me fall asleep.”

“I-I see…  Yes, I suppose being too energetic could be difficult to deal with.”  Nodding but avoiding eye contact, Murasaki’s face turned an even brighter shade of red.  “I also came here to move my body a bit while nobody else was around.  Loathe as I am to admit it, sometime I can’t help but envy the strength and capabilities of so many other Servants.  As much as I’d love to stay in the library and read, I wouldn’t be able to face Shōshi-heika or Michinaga-sama if I failed to properly support you, Master.”

“Oh?  It is pretty rare for you to leave the library for more than meals or a mission.  I guess if you just sit around and eat all day, even a Servant would be concerned about things like that.”  Chuckling at her surprisingly normal concern, Ritsuka offered her a cheerful smile.  “But everyone has things their own strengths and weaknesses, right?  Even if you’re a bit clumsy on the battlefield sometimes, I couldn’t hope to match you in your Mana Capacity or the potency of your Onmyoji techniques.  Still, if you want someone to join you, I think it’d be nice to train with someone closer to my level.”

Puffing out her cheeks and furrowing her brows a bit, the voluptuous Caster crossed her arms under her bosom and looked away from him, pouting.  “While I thank you for the compliment, Master, I dare say that I am still quite active, even if I limit myself to my duties as head librarian majority of the time.  Why, I would even wager that if we were to compete, I would handedly defeat you.”  She said, turning back to face him, leaning forward, and pointing at him with a hand on her hip.

“M-Murasaki-sensei?  I’m sorry if I said something to offend you.”  Caught off guard by the older woman’s attitude shift, Ritsuka tried to de-escalate the misunderstanding.  It wasn’t like she was genuinely mad at him but more akin to a child getting frustrated at being told they couldn’t do something and becoming determined to prove the offending person wrong.  “Running the library isn’t just mentally tasking, but physically too.  Running back and forth through the shelves, carrying stacks of heavy books, breaking up fights to keep the order.  It’s still a pretty demanding job.”  She usually keeps a cooler head than this.  I just something really is bothering her…  He thought, trying to find the words to apologize.

“Hmph.  Perhaps, but you seem to be taking me too lightly.  After all, I am still a Servant.  So, are you willing to test yourself against me?  Push-ups, sit-ups, running laps, and I hear that modern Mages have adopted practicing some form of martial arts, yes?  We’ll end our competition with some sparring.”  Murasaki said, not giving Ritsuka a way to back out.  “The winner can decide on some reward or punishment if they want.  What do you say, Master?”

She can’t be serious, can she?  She’s about as athletically capable as Stheno or Euryale, though her Endurance does increase a bit if she’s completely changed her class to Rider.  Considering just fully apologizing and asking her to forgive him, Ritsuka tried to consider her physical abilities if she wasn’t boosting them with her onmyoji spells.  At the end of the day, Murasaki Shikibu was just a novelist from the Heian period with some knowledge of Eastern Magecraft.  She wasn’t a warrior or gifted with a Divine physique, though her figure was definitely one that was blessed by someone.  It would be mean of me to go all out after all the training I’ve done, but hopefully, if I keep it close, she’ll feel comfortable asking me to train with her again.  “Alright, Sensei, four events.  Winner decides the prize.”

Shaking on their agreement, they went to the side where there was room for calisthenic workouts, and they got into position to do push-ups first, facing one another.  With less than a foot between their faces, Ritsuka tried to focus his attention on her enchanting, deep purple eyes, which would normally be easy.  But as they began doing their push-ups, he couldn’t help lowering his gaze as her large breasts squished against the floor.

My Gods, they’re no smaller than Mama Raikou’s…  No, they might even be a bit bigger.  Unable to not see how the masses of soft flesh and fat squashed out as she lowered her body onto them, they left an impression on the floor where they wiped away some dust.  N-No, no…  I’ve got to focus on the competition.  If I outpace Sensei too much I won’t be able to… huh?  Reminding himself of his goal, Ritsuka focus on the rest of her body, in particular her slender arms, to gauge how much she was straining.

“Fifty-five, fifty-six, fifty-seven...”  With no noticeable change to her breathing, the mature Caster was lowering and raising herself in time with him.

She’s keeping up with me?  Well, I was a bit distracted.  Her performing better than he excepted helping to keep his head in the game, the strain in Ritsuka’s arms was slowly building, but usually by now it’s a bit worse.  “Wow, I didn’t realize we were already in the fifties.  You’re doing better than I thought, Sensei.”  He said, trying to engage in some friendly banter.  He still didn’t understand why she was so upset with him, but she seemed to be more on guard with him.

Pausing for a moment so she didn’t lose count, Murasaki looked at him with a slightly puzzled expression.  “Weren’t you keeping track of your progress, Master?  You were going a bit slower than me for a while, so you’re quite a bit behind.”  She said plainly, shifting her weight on her hands since she had a moment, which caused her breasts to jiggle quite a bit.  “I believe you should be somewhere in the thirties right now, but I wasn’t keeping a close eye on it, sorry.”

“Thirty!?”  Judging from the exhaustion building in his arms, the young Magus figured she wasn’t trying to deceive him.  Crap, I really got distracted!

“Oh… U-Um… Maybe I’m mistaken and you’re close to forty?  All I know is that you slowed down for a bit, so you’re not past me.”

“What?  Oh, no, I wasn’t questioning you, Sensei, I just didn’t think I was that far behind.  Maybe I’m a bit more tired than I thought.”  Rather than rush to catch up to her, Ritsuka chuckled meekly and got back into a good rhythm for himself.

Motivated to not lose face after what he had said before, the dark-haired young man pushed himself to keep up with the literary Servant, breaking his previous record and getting up to one hundred and fifty push-ups before his arms finally gave out on him.  Murasaki, however, was still ahead of him and continued on until she hit two hundred before stopping.  Pulling her legs up under her, she gracefully knelt and used her towel to wipe away the light amount of sweat she was perspiring.

“Maa~ Master, that was quite fun, was it not?”  She asked in a lightly teasing tone.  “Though, since I don’t get out of the library too often, my body feels a bit stiff.  Otherwise, I could have kept going a bit longer.”

Slowly picking himself back up, though his arms were screaming at him, the pain paled in comparison to the stinging comment she made.  His shirt and shorts were drenched in sweat and grabbing his water bottle, he had to resist the urge to chug it down.  She barely broke a sweat, so she’s probably not bluffing.  However… y-yeah, isn’t her chest kind of like cheating?  I mean, every time she lowered herself, they’d take some of her weight off her arms, right?  But I’ll be nice and-

“Ara!  That’s right.  Sorry, Master.  Even though you workout much more than me, you weren’t able to match my record, were you?  Ufufu, perhaps your muscles are just for show?”  Adding an extra playful jab that had a bit more bite to it, she interrupted his thought, giggling childishly.

Eye twitching, Ritsuka took another big swig of water from his bottle before setting it aside.  You want a ‘show’, do you?  Standing up, in one smooth motion, the young man was able to peel his sweat-soaked shirt off, tossing it to the side.  He then picked up his towel and began to wipe up his sweat.  “That was just the first one, Sensei.  I’ll catch up, you’ll see.”  Looking back and seeing her turn away from him, face and ears burning bright crimson, he smirked at the small victory.

“M-M-Master!?”

“Hmm?  Oh, sorry, Sensei, but a wet shirt is uncomfortable.  I hope you don’t mind my ‘display’ muscles.”  He joked back at her.

There was a short silence between them as Murasaki steadied her breathing before standing up herself.  “No, you’re right.  This does feel much better.”

“Huh?  What do you me-!?”  Turning to face the older woman, Ritsuka’s eyes nearly popped out of his head when he saw that the dark grey, vertical-striped underlayer of her swimsuit had been removed.  The shiny black layer was still on, which coverer the naughtier bits of her breasts, butt, and crotch, but her cleavage, underbust, back, and large percentage of her stomach were now bare to see.  Though still blushing slightly, she was using her towel to dry between her breasts, which was significantly sweatier than her arms and legs, likely because of the layer she took off.  “S-Sensei!?”

“Hm?  Ara, Master.  Is something wrong?”  She asked, looking at him with a mischievous smile.

“N-No.  Let’s just move on to the sit-ups.  Whoever does the most in a minute wins, okay?”  He said, turning away to remind himself to breathe.  W-Were her eyes glowing just now?

“If you say so.  I’ll let you go first and hold your feet for you.”

Nodding, Ritsuka laid down and pulled his feet a bit closer to his butt.  Murasaki knelt down and planted her hands on his feet so they wouldn’t move.  “Thank you,” he said, as he put his hands on either side of his head without touching it.  Working his abdominal muscles, he curled his body up until he was sitting.  “One-!”  Counting to keep track of his progress, Ritsuka froze for a moment as he saw the view that would be waiting for him with each repetition.

The dark brown-haired beauty kneeling with her hands down, squeezing her large breasts between her arms as she looks at him with a lovely, alluring smile.  The mischief she was plotting only enhanced her elegance, beguiling him with the blush dying her cheeks.  The sheen of sweat gave her pale skin an arousing luster, and given how little skin she usually showed, had an even bigger impact on his pent-up youthful vigor.

“Master?”

Her voice both breaking him from his trance and ensnaring him with its light timbre, Ritsuke shook his head to clear it of the multitude of unsavory thoughts fighting to take form as he lowered himself back down.  Sensei’s body is having a bigger impact on me than I thought it would.  It’s because she’s usually all covered up, and even then she’s sexy as hell!  There’s no shortage of beautiful women in Chaldea, but Sensei is…  Closing his eyes to try and control himself, Ritsuka continued his workout.  “Two, three, four…”

With a fumbled start, Ritsuka tried to speed up to make up the difference.  During normal training, exercises like push-ups and sit-ups were done in repetitions and sets to maximize their effects and minimize injury, so he wasn’t used to pacing himself in such a competitive manner.  However, with his eyes closed, he didn’t need to worry about the distraction of Murasaki’s plump, shapely body… those the image of her breasts and thighs was still fresh in his mind.

Thankfully, the more sit-ups he did, the more his muscles burned in protest, which served as the perfect distraction to his lewd thoughts.  “Fifty-three, fifty-four, fifty-five, fifty-six, fifty-sev-”

“T-Time.  That’s o-o-one minute, Master.”

Mid-crunch, his muscles refused to push themselves anymore after hearing the gentle woman’s voice.  Ritsuka flopped back down onto the matted floor, breathing heavily to replenish the oxygen he used up.  “Fifty-six and a half.  But I don’t think halves count.”  Chuckling, he held his stomach and slowly opened his eyes, staring up at the ceiling.  “Just give me a second, Sensei, and I’ll spot you.”

“Y-Yes, Master.  Take your time.”

Why’s she stuttering all of a sudden?  Rolling over so he could pick himself up without working his core too much, Ritsuka looked at the Caster as she averted her gaze, blushing intensely.  Shit!  Am I!?  She was embarrassed by something about him, so with his thoughts being so indecent, he looked down at his crotch.  Mercifully, he wasn’t hard enough to make it noticeable.  Because of how intimate most of the other female Servants training him got without regard for his easily stoked libido, he had taken to wearing tight boxer briefs under loose-fitting shorts while working out.  With his blood plumping all throughout his body, little had a chance to embarrass him.  I don’t know which god I should thank for that, but that doesn’t explain… well she’s been acting a bit weird since she came in.  Unable to understand his Servant, there was something oddly cute about how she fidgeted as he caught his breath.  “Alright, your turn, Sensei.”

Nodding as he crawled over to her, Murasaki laid down on her back and got into position to do her sit-ups.  Her face was still a light shade of red as she avoided looking Ritsuka in the eye, readjusting her feet to be slightly more apart as he held them down for her.

Applying his weight on her feet, the smooth, soft texture of her skin caught the young Magus off guard.  Looking down at her ankles, the sheen on her hairless, blemish-free shins made her long, slender legs look lovely in the fluorescent lights.  Such cute, slim feet… they fit right in the palms of my hands.  And her skin, as pale as the moon.  Sensei was widowed young, right?  Her husband was a lucky man.  Silently admiring Murasaki’s legs, Ritsuka stabilized himself as she began she exercise.

“One, two, three, four…”

The shadow of her body rising and falling and the impact of her weight shifting from moving forward to back quickly caught his eye and unwittingly, Ritsuka’s gaze slowly climbed.  Unable to look away, her plump thighs tightened to assist in pulling her torso up, quivering as she reached the apex, and relaxed as she lowered herself back down.  With her belly and breasts partially exposed, seeing her flat stomach constrict and relax, showcasing the subtle, supple muscles beneath was a treat for the eyes, and the constant motion and her breasts jiggling and bouncing against the restrictive material of her bathing suit.

However, his eyes had been drawn away from her captivating chest.  Framed by her thick thighs, and kept barely modest by the shiny, thin fabric of her clothing, without the additional layer of the swimsuit to mute the details, her plump womanhood was all but plainly visible.  The deep, vertical slit ate up part of the crotch of her bathing suit, almost completely exposing one of her vulva while the shape of the other bulged out from under its covering.  Sen-!?  Paralyzed from the erotic display before him, Ristuka couldn’t think straight as his mind took in all the details.  The jiggle of her skin, the drops of sweat that pooled in the creases of where her thighs met her pelvis, how the hefty cheeks of her backside were split by the bunched-up swimsuit, and the short, wiry hairs that barely poked out from the side of her clothing.  His proximity to her also meant that with each repetition, the air surrounding her was laced with a bit more of her scent.  Whatever force that was keeping the young man from becoming erect could no longer hold back his lust, and his underwear strained to contain him.  Each sit-up caused her bathing suit to slip a bit more, closer to the center and digging into her soft folds.  Just a bit more and…

“T-That’s e-enough, right, Master?”  Falling onto her back, Murasaki kicked her legs up as she finished, consequentially throwing Ritsuka back a bit as well.  “Sixty-eight.  I’ve won again.”

“R-Right, right!  G-Good job.”  Thankful for the jolt to break him from his unsavory thoughts, Ritsuka sat up in time to see Murasaki manifest the underlayer of her bathing suit again.  Yeah… that’s probably for the best…

“W-Well, Master, if you don’t try a bit harder, I might have to g-give you a more severe p-punishment should I ‘sweep the competition’, as they say.”  Quickly standing up, she adjusted her clothing to fix the parts that had slipped out of place, poorly hiding her embarrassment with a smug tone.

Picking himself up and stretching his legs a bit, Ritsuka smirked at her confidence.  She trips over her feet all the time in battle, so this one should be easy.  Using the time she took to fix her clothes and catch her breath, he calmed himself down before she wasn’t the only one to have a near wardrobe malfunction.  “Don’t worry, Sensei.  I’ve seen your clumsy side enough, so if you trip, just pick yourself back up.  Okay?”  He said as they approached the running track, matching her playful jeering with his own.

“H-Hmph, the only side of mine you’ll be seeing, Master, is my backside.”  Blushing almost immediately after she replied without thinking, Murasaki covered her face with her hands as blush colored her face again.

“Maybe after I lap you.”  Trying to diminish her embarrassment a bit, Ritsuka turned the comment back on her as they lined up.  “Ready?”

Pulling some of the material of her swimsuit that was giving her a wedgie out of her rear, the dark-haired woman nodded, trying to not look at him.  “Ready.”

“Alright, first to finish ten laps win.”

“Yes.”

“On your marks.  Get set.  Go!”

Signaling the start of their race, Ritsuka didn’t sprint at the start since the track was one-hundred meters long.  One kilometer was a long way to sprint, so he was going to pace himself and save his energy for the last few laps.  Murasaki, however, exploded from the starting line with a huge burst of speed, leaving him in her dust, and true to her word, only showing her back and full, round rear to him as she quickly rounded the bend.  Okay…  I wasn’t expecting Sensei to be that fast… but that’s a rookie mistake.  Sprinting like that, she’ll be out of breath by the fif-

“Ara?  Master?  How did you get in front of me already?”  Hearing Murasaki’s voice come up from behind him just as he was exiting the first bend, Ritsuka looked back to see her smiling confidently at him.  “I thought you said you were going to lap me, yet it seems that I am the one,” effortlessly passing him, she giggled at him, her breathing not disturbed in the least, “lapping you.”

As she pulled further and further away, Ritsuka's thoughts were split between how much her butt was stretching the material of her bathing suit as she ran, it slowly sliding deeper between her pale, hefty cheeks as she ran, and the speed she was displaying.  How is she so fa-!?  Oh…  Oh no…  Trying to figure out how she was outpacing him so easily, Ritsuka recalled what the mature Caster’s Parameters were.  I still don’t know if she’s fully changed her Saint Graph to turn into a Rider, but how could I forget that as either a Caster or a Rider her Agility is D Rank!  Allowing the near-human levels of strength and endurance she typically displayed to blind him to the superhuman speed she had at her disposal, as far as a Servant it concerned, Murasaki’s physical stats are pretty low.  But ‘pretty low’ is relative!  I might as well have challenged a car to a race.

Watching as she quickly ran another lap around him, Ritsuka thought about how he had spoken to Murasaki earlier, underestimating her physical abilities just because she stayed in the library most of the time.  Her irritation and cutting words made sense now.  Just because she doesn’t pride herself in her physical capabilities didn’t mean that she’d stand by when someone, intentionally or not, insulted them.

I’ll apologize properly after this.  He thought as she came up behind him once more.

Lapping him again, Murasaki continued ahead of him a bit more, then slowed her pace to keep a certain distance between them.  “Enjoy the view back there.  I pr-promised you you could.”

There was something oddly refreshing seeing such a mature and composed woman acting so childishly.  Even though she could easily continue on and finish her laps in a fraction of the time he’d take to do his, she kept her lead on him without increasing it any further.  It was playfully insulting and a complete show of dominance over him, but Ritsuka didn’t mind.  Whether she realized it or not, the bathing suit was riding completely up her butt by now, so he had a clear view of the ripples each step shook her plump backside with.  Even when he picked up his pace for the final three laps, she maintained the distance she set between them, and ran the two extra laps just because she could.

Dropping to the floor, exhausted and gasping for air, Rituska’s defeat was settled.

“U-Um…  Master?  Are you alright?”  Sheepishly approaching with a towel and his water bottle in hand, other than a light sweat, Murasaki was still perfectly fine despite running twelve-hundred meters.  “S-Sorry.  I may have taken this a bit too far.”

Looking up at the busty librarian as she bent over to offer him her olive branch, Ritsuka’s newfound depths of respect for her only made her all the more alluring.  Sitting up, he took the towel and drank the water as he tried to get his breathing and heart rate under control.  “Not at all Sense- no, after all this, I can’t keep treating you like some delicate lady who hasn’t lifted anything heavier than a book.”  Turning to face his Servant, his genuine regret over how he had treated her reflected in his pure eyes, Ritsuka bowed until his forehead touched the floor.  “Thank you for the lesson, Mura… Kaoruko-senpai.”

“K-K-Kao-!?  S-Sen… pai?”  Unsure how to respond, Murasaki took a few steps back, clutching her chest as the words died in her throat and her face turned the brightest shade of crimson yet.  “M-Ma-M-Master?!  Wh-W-Why would you…?”

“Hmm?  Well, it was either senpai, onee-chan, or aneki, since I can’t really see you as an obaa-chan.  Also, you’re not really a formal instructor of martial arts, so sensei and shishou don’t really fit either.”  Not expecting such an extreme reaction, the young Magus chuckled at how adorably embarrassed she was acting as he explained his thought process.  “You wrote your poems and novels under your descriptive name, but seeing you as ‘Murasaki-sensei’ had me underestimating you, so I thought I’d change how I refer to you.  Do you not like it?”

Holding back her tears, Murasaki quickly approached and embraced Ritsuka tightly.  “O-Of course it’s fine, Master.  But… could you just call me ‘Kaoruko’ instead?  I don’t think my heart could handle anything else.”

With his face next to her and an impossibly soft feeling on his chest, Ritsuka returned her embrace, more embarrassed by it than calling her by her name.  “So… I might not be able to win our competition anymore, but would you still like to spar, Kaoruko?”

“Huh?  B-But Master…  After what I did.”  Not wanting to put him through anymore, the busty Caster was ready to just call it a night there.  Though going a bit overboard, she taught her handsome, young Master the error of his hubris.  “I couldn’t p-possibly…”

Standing up, Ritsuka smiled softly at her and lead her by the hand toward the wrestling mat.  “Just because you have the advantage physically doesn’t mean you’re sure to win.  If there’s anything I’ve learned since joining Chaldea, it’s that in a match, it’s usually the smarter and more experienced fighter that will win.”

“W-Well… I suppose…”

“Don’t worry about it.  Nobody else really holds back when they train me…”  Chuckling emptily as his eyes went vacant for a moment, Ritsuka thought back on all the grueling training he had been through so far.  “At least… I hope they don’t think that’s holding back.  So, give me your best shot.  Or does ‘Murasaki-sensei’ want to go sit down and read already?”

Though his tone was playful and not at all disrespectful, just a little jab to motivate her into agreeing.  “Never mind, Master.  Perhaps I’ll have you call me ‘Kaoruko-sensei’ once I’m done teaching you a lesson in respecting your elders.”  Smiling menacingly as her deep, purple eyes looked to glow in the shadows cast by her bangs, she giggled darkly as she rose to his obvious provocation.

“Alright.  We’ll go until one of us gets the other to say they concede.”

“Maa~  That means I can take my time, yes?”

“I’ll apologize now in case I end up touching you somewhere inappropriate.  Shishou tells me that, if I have an opening, I shouldn’t hold myself back.”  Getting into a fighting stance, Ritsuka made his intentions clear that, while he was going to try and fight clean, he wouldn’t hold back if it meant he could win.  “Let the match, begin!”

Very quickly the difference in skill and experience made itself apparent.  After years of receiving instruction from so many talented warriors and mentors, someone with as little practical knowledge of martial arts like Murasaki was easy to feint and trip up.  Offsetting her stances and unbalancing her root meant that, even when she tried to counter-attack, he could slip away.  Her unpracticed movements were easy to read, and hesitation kept her on the defensive, allowing him to make contact despite the difference in their speed… but a Servant’s Agility stat is more than just a measure of speed.

Even if his maneuvers and feints caused her to flinch away or curl up defensively for a moment, her reflexes allowed her to recover before he could land a solid attack.  As such, even her mistakes left openings too brief to fully commit to any sort of attack.  Worse yet for the young Master was that the longer their match continued, the more accustomed Murasaki became to his tactics.  She was hesitating for shorter periods of time and less frequently, sometimes even inviting an attack so she could capitalize on a blunder.  For a woman that served as a lady-in-waiting and novelist for her whole life, she wasn’t completely unaccustomed to combat.

Well, I suppose that makes sense.  She did live during the Heian period, which was full of dangers and Mystic.  Ritsuka thought as his fatigue was beginning to catch up with him.  It was already late and he had come to the gym to tire himself out anyway, so he didn’t really have much energy left.  Evening in the Edo period more than five-hundred years later, Munenori said that Kasuga no Tsubone's skill with the naginata inspired some of the forms he developed into his Shinkage-ryuu, and she was a wet nurse.  It wouldn’t surprise me if Kaoruko received some martial arts training along with the onmyoji arts she learned.  Wiping the sweat from his brow, Ritsuka contemplated his next move as he tried to catch his breath.  There were so many openings and flaws in the Caster’s stance, but her reflexes were making up for her lack of experience.

She was becoming more sure of herself, shedding the nervousness that she had been trying to conceal with aggravated confidence, and seemed to be enjoying herself.  Maybe even a bit too much.  Whether she was letting her advantage get to her head, or her adrenaline was making her get a bit carried away, it wasn’t often the humble novelist acted in such a gloating, domineering manner.  At least, not when certain individuals that she just couldn’t get along with weren’t involved, or someone caused a bit too much mischief in her library.

At this point, all I can do is go for a grapple and pin her.  With his options and strength limited, Ritsuka opted for one of the few strategies left to him.  Thankfully, her raw strength was more comparable to a normal human’s, as opposed to the Demi-Gods and legendary warriors that could stand with ease even if he got them into an arm bar hold.  Rushing in, he ducked under the telegraphed palm thrust that Murasaki threw, spinning around and extending his leg to knock her forward foot out from under her.  Once she hits the mat, I’ll grab her arm, and then-?!

“Ei!”  However, as his heel approached her, faster than he could react, she pivoted on her foot and jumped back into him.  “Hah!”  Delivering a powerful, hip check to his cheek, Murasaki had gotten a clean hit in on him finally.

There was nothing Ritsuka could do to protect himself from such an unexpected attack.  As he landed on the mat, his momentary disorientation left him open as the dark-dressed woman sealed his arms under her shins and grabbed his legs, locking them under her arms.  Her breasts squished against his crotch as she secured her hold and sat up, and by the time Ritsuka was able to shake off the impact of the blow, he was caught in the shadow of her large, soft backside.  “Kao-!?”  Flabbergasted by the erotism of the grapple she chose, it was also effective in sealing off his movements.  The plump roundness of her backside, the depth of which was consuming much of the material meant to cover the pale moons, and the bulge of her nethers squashed by the tightly stretched bathing suit stole the words from his mouth.

“Ara~  I must say, Master, perhaps you were right about me.  All this moving is quite tiring.”  Teasing as she restrained him, Murasaki looked over her shoulder down at him with a seductive, enthralling smile.  Like a predator proving their superiority over their prey, her smile promised that if he was going to get out of her grasp, it would be because she allowed him.  “I may not have a good book to read at the moment, but you won’t mind if I sit and rest for a while, will you?”

The meaning of her words taking a moment to register through the lustful thoughts overwhelming his mind, Ritsuka’s eyes widened as she began to drop her hips.  “W-Wai-mmph!”

But Murasaki did not wait, nor did she stop short and tease him with her backside.  Plopping her rear firmly down, she buried his face deep in her soft, warm cheeks.  And with him trying to ask her to stop, much of her womanhood bulged into her mouth, preventing it from closing!  The scent of her sweaty backside filled his nostrils, contaminating his lungs with her sweet, heavy scent, and while his tongue didn’t caress the swimsuit-clad sex that pressed against it, there was a tangy flavor that mixed with her sweat.  Grinding her butt into her face to settle her full weight onto him, she let out a satisfied sigh as her body quivered in delight.  “Maa, yes, I must say I am most comfortable sitting, as you mentioned, Master.  And finding a good seat just makes you want to settle in for a while, does it not?”  Giggling, she held the unresisting young man under her, forcing him to breathe in her aroma before raising her hips a bit.  “Well, is there anything you wish to say, Master?  Or is our match continuing.”

Shaking his head to get his wits about him, Ritsuka looked up at the perfection that was Murasaki’s rear, deeply regretting what he was about to say.  But as her Master, he couldn’t take advantage of her like this.  While unconventional, with was a legitimate submission hold and she had bested him.  “I gi-mmph?!”  However, before he could concede, she dropped her butt onto him again, cutting him off.

“Hmm?  What’s that, Master?  I couldn’t quite hear you.”  She said playfully.  “Maybe this will get you to give up.”

Ka-Kaoruko!?  Buried under the beautiful woman’s full backside again, while he had the opportunity to close his mouth this time, it seemed as if more of his face was getting covered by her pale cheeks.  Not to mention that he hadn’t taken the chance to clear her sweat-laced air from his lungs.   At his limit, Ritsuka was forced to deeply inhale, his body not caring how greedily it needed to do so to get some fresh oxygen.  With how much he had been exerting himself, he couldn’t be reserved and sniffed the deepest crevice of the Caster’s backside while trying to free himself from her hold.

“Still resisting, Master?  Well then, keep it up for as long as you can.”  Tightening her hold, Murasaki pulled his legs closer to her body, causing her chest to spread around his groin more.  The quivering of her body had her hefty cheeks lightly slapping his face, and her voice was getting deeper and more sensual by the moment.  “You c-can be so stub-b-born sometimes, Master…  B-But that’s one of r-reasons you’re so wonderf-ful.”

The way she was grinding her undercarriage against his face began to melt Ritsuka’s sense of reason.  There was only so much a healthy young man like him could do to control himself in such a compromising position with a beauty like Murasaki.  The only thing separating their bodies were thin layers of fabric, which did little to mute the stimulation he felt.  She raised her backside a couple more times, giving him a chance to concede, but every time he tried, she’d swiftly drop her hips again to silence him.  And he couldn’t deny that he wanted this to continue too, especially after the stimulating day he had already gone through.

However, eventually, Murasaki released and dismounted him, covered in sweat and breathing just as heavily as him for once as she laid next you him and gently placed a hand on his chest.  Bringing her lips close to his ear, she giggled and whispered to him, “Well, Master?  Are you ready to concede now?”

In a daze, Ritsuka didn’t think of anything other than the elegant Servant’s words.  She had proven herself to be stronger, faster, and superior to him in combat so easily.  He wasn’t even able to give up unto she allowed it.  For a Servant that typically listened to him so well and acted in a much more reserved manner, her methodic domination of him was all the more effective because of it.  Closing his eyes and envisioning her meaty rear above him again, Ritsuka nodded.  She had defeated him utterly.  “I con-”

“I concede.”  Cutting him off, Murasaki resigned first, giving the victory to him.

“Huh?  Kaoru-!?”  Turning to look at her, Ritsuka was about to question her but was stopped as she placed a slender finger to his lips.

“Shhh, Master.  I know what you want to say.”  She said as she smiled gently at him.  “But this doesn’t feel right or fair of me at all.  After all, I could have simply done this, and you wouldn’t have been able to fight back at all.”  Activating her magic circuits and concentrating the flow of Mana into the hand resting on Ritsuka’s chest, she firmly held him down with a pressure that, while didn’t crush him, prevented him from being able to move for a few seconds.  “You are undoubtedly a more skilled warrior, so I don’t want you to think otherwise.”

The humiliating defeat under her backside starkly contradicting that notion, Ritsuka couldn’t deny that he had fared better against her than he would have before coming to Chaldea, so he could try to be proud of his progress.  “Man…  I thought I’d at least stand a better chance against a Caster.  I always end up forgetting just how big the gap between humans and Servants is.”

Giggling as she sat up, Murasaki held up her hand to dangle a finger over his chest.  “Well, Master, if you want, I’ve just thought of a way to demonstrate that difference, if you want.  Though, I’ll have to curse you a little bit to do so.”

She calls it a curse, but…  Nodding, Ritsuka smiled at her.  “Alright, Murasaki-sensei.  I trust you.”

“Uh ah ah, Master.  Don’t you remember?”  Focusing her magic into the tip of her finger, Murasaki drew a circle with a five-pointed star inside of it and leaned in again to whisper in his ear.  “I believe I said I’d have you call me ‘Kaoruko-sensei’, did I not?”

The intimacy in her voice as she spoke distracted Ritsuka as her magical energy coursed through his body.  Even though he started saying it as a respectful acknowledgment of her being more than an unathletic novelist, referring to her by her given name was more embarrassing than he thought.  “R-Right, Kaoru…ko?”  Before he realized it though, everything around him had become much, much bigger, the beautiful, purple-eyed Caster included.  With her face so close, she could easily gobble him up, he had become so tiny!  “Wh-Whoa!  What happened to me?!”

“Hmm…  I can still hear you, but your voice is really quiet, even from this small of a distance.  You might want to communicate with me telepathically while your at that size, Master.”  She said, getting on her hands and knees as she observed him closely, smiling gently.  “You should be around six or seven centimeters tall right now.  Excluding a few exceptions, this is about how big the gap in overall abilities between you and us Servants is.  I understand that you have become much stronger since becoming a Master, but thinking you can face a Heroic Spirit is dangerous.  I hope you’ll learn from this and not make the same mistake in the future.”

Six centimeters…?  That’s still smaller than the difference between our usual heights.  Mura-er, Kaoruko isn’t a small woman, but she looks absolutely massive right now.  Taking in the full scope of what she was demonstrating, Rtisuka didn’t just look at her, but the rest of the room as well, and just how tiny he had become.  Well, yeah.  If I saw someone as big as her standing in front of me, I’d never think about challenging her to a competition.  It’s no wonder Mages thought up Command Seals to keep their Servants in check.  If she sat on me now…  The image still so vivid in his mind of her flawless rear hanging over his head, this time enveloping his entire field of view and coming crashing down and covering him completely, Ritsuka swallowed the accumulating saliva in his mouth.  The scent of her breath surrounded him, whatever tea she paired with her evening reading carrying and mixing with her potent sweat and arousing pheromones, drive his heart to go wild.  “Yeah, this definitely illustrates the…”  Trying to distract himself from the lewd thoughts of her sitting on him and more, Ritsuka was about to agree with what she was saying.  But the warm breeze of her breath washing over him caressed his stiffening member a bit too strongly for him to ignore, and when he looked down, he realized that his clothes hadn’t shrunk with him!  “Kaoruko-sensei!?  Wh-What happened to my pants?  No, never mind.  Just change me back, quick.”

Bringing her finger down onto his chest, Murasaki’s playful laughter transitioned into a sultry giggle as she stared down at him with amorous eyes.  “Maa~  Now Master, you have nothing to be embarrassed about.  In fact, you should be quite proud.  Even with clothing on, you were able to pierce my chest quite deeply earlier.”  She said in an endearingly teasing tone.  “Besides, someone’s commentary is being more honest.”