(Reader Beware: This is a Yukari x Reader weight gain thing. I wrote it all in one sitting in an episode of severe hag fever.)
It was a bright cold day in April, of the ordinary and otherwise unnotable variety. Walking around the wherever you walk around, going about your chores and business and life's drudgeries, so on and so forth, until... a sudden gap in reality appeared and swallowed you whole. A purple rip in the ground, strikingly unfitting and unreal compared to its surroundings. Surroundings which ceased surrounding you all of a sudden as you fell into the gap.
"Hey you. You're finally awake."
A woman's voice, cutting through the bottomless purple darkness. The surroundings became clear again. A towering presence, with her glimmering golden hair and vibrant purple dress. An old woman to be sure, with her wrinkles, thorns, and a bit of flab, but a powerful, beautiful one nonetheless. An elegant hand, covered by a white silken glove, grips onto the cup of tea which she sips on. The room is empty save for the two of you. Empty and dead quiet. You are not sure whether this is real or you are having a severe case of psychosis. Maybe it's both. An eternity passes, or so it seems at the least. Not receiving any word from the woman, you get up to look around and perhaps leave.
"Now, now. No need to leave so quickly. Please, won't you accompany a lonely old lady for a bit?"
She does nothing to stop you or drag you back, but… curiosity does oft get the better of mankind. There should be no harm in getting her name at least.
"Oh, I thought you'd never ask. Yukari Yakumo. You may call me Yukari, dearie."
An odd name, for an odd woman. Why would she even summon you?
"Hmm… Well, if you intend to leave, there'd be no use in me telling you. Come, sit down, I'll have my servant bring you tea as well."
A servant? So it isn't just you two. She claps her hands and summons a woman with a… very pointy bonnet. Oh, and she also has several tails protruding from her dress. Compared to the eldritch gaps though, this is not that weird. Fish might as well begin climbing poplar trees at this point, and it wouldn't amount to much surprise. She leaves a cup and a pot of tea for you, plus the required extra pastries for a good tea time. Crumpets, scones, such and such. A moment of hesitation does come - these might be poisoned after all. Then a moment of realization, in that a woman who can summon rips in reality out of nowhere could as easily rip you to shreds. She wouldn't exactly need to resort to such underhanded tactics, so, down a cookie goes for taste-testing.
It proves quite delicious, easily the best you've had in recent history. So are the rest of the pastries, which combined with the warm tea, go down very easily. The old lady accompanies you by sipping her own tea, and courteously filling your cup up when it's emptied. You don't exactly remember how much you snacked on, but it certainly feels like it was a whole lot, especially as her fox servant brought more and more. Some small talk does occur during the dining, but it is very small. The old lady is vague, not telling much about herself, but the tales she tells are tall and captivating. Riding in the steppes, traveling the Far East, meeting this and that… she seems to enjoy the talk, and enjoy even more your awe and confusion. Yukari giggles very faintly, very subtly, yet it hides much amusement that spills through the exterior.
"It's getting late, dearie. Won't you stay the night at our guest room?"
There are no windows looking outside, or any clocks to read the time, but your body does feel heavy. Yukari hasn't proven to be any hostile, only mildly infuriating to talk to, so there seems to be no harm in accepting. Her servant, who is apparently named Ran, leads you to said room and bids you good night.
Tomorrow, when you wake up, it's with breakfast in bed. Quite the luxurious welcome for… well, you're never told to reason. That holds true for the evening, and lunch, and for night when it's teatime again and you fall asleep after small talk with Yukari. So it goes on for the next day, and the next day after that… when you get bored, you find some books and magazines by your bed. A few days after, an old television set up with a disc player and a few shows to watch. Some pencils and papers to draw, or maybe an instrument that you know how to play, things to cater to whatever hobbies you might have to pass the time.
The one thing that doesn't change is the delicious food. At a certain point, you notice that Ran will bring whatever you want whenever you want as long as you ask. The offer of free food comes with much temptation, and rounds of snacking are now added on top of the regular meals that were already hearty. That doesn't come without its consequences, especially as there isn't much you are doing to burn the food away. Even if you did, there is a lot going in. First, a feeling of tightness around the waist, as the clothes you came in with start to fail to contain you. That somehow disappears one day, your clothes having been refitted overnight. Again and again, as you grow, you wake up to slightly bigger clothes. They're still the ones you arrived in just… somewhat bigger. A little bit bigger than last time, and there happen to be many "last time"s that pile up over your stay. Your gut pushes out, first from a bit of rotundity to a conspicuous hang, covering more and more of your lap every day you wake up. A fatter hindside that sometimes struggles to navigate through the tight corridors of Yukari's estate, legs that now waddle rather than walk, arms that tire with a simple motion of grabbing at the offerings…
It's not clear whether it's been weeks, months, or years, but time seems to pass quickly, and equally quickly do you yourself change at the hand of the old lady. She is always as outwardly aloof, mysterious, yet subtly affectionate. "Don't worry about it, enjoy yourself, dearie~", "Aww, can't I treat you to a little more? Come on~", "Please, you're my guest~", so on and so forth.
One day, you are summoned, to the living room where you had first appeared in. It's a bit harder to find somewhere to comfortably fit and seat yourself, with the you in question being much much larger, but you eventually manage. It's like the first time, there being nothing but tea and Yukari.
"Now, I will be straightforward." An unusual sentence to hear from a woman who is anything but. "I know you have been dying to hear why I had summoned you hear in the first place. It's quite elementary, dearie… I was simply bored and wanted somebody to play with! Ahaha~" She really seems to enjoy seeing a shocked, or disappointed, reaction. She cackles as she watches your reaction. "Now, I believe I have kept you occupied for long enough... I was planning on letting you go whenever you wanted to go, but you forgot to protest. What a perfect little pet you are~ We'll definitely meet again soon."
Without giving you a moment to respond, you fall into the purple darkness again, and reappear wherever you had first disappeared from. After a moment of shock, the first reaction of any 21st century person is, of course, to check their mobile phone. Not a single day has passed in the outside world, and yet… your body is not the same as you left it. Much heavier, even struggling to stand up in the middle of wherever now… you don't even want to think about how you'll explain what happened to your acquaintances now that you have come back. The only other thing left on the phone is an open Notes app, with one more note that had been added and saved today:
"Leave a few pieces of fried tofu by your bed, and my servant will take you back. Come back soon and better don't leave your old woman alone, okay?"
