Mercie's sweetest tooth♡ (Patreon)

$20 Dollars commission, Mercedes benz from FE: Three houses! 

And here's the Story/Description:

 “Aaaaaaarp!!!”

The future king of the kingdom of Fodlan, Dimitri, said as he walked inside the dining hall, it weird for him to do some midnight strolls, and incidentally, as he was walking by, he heard a sound echoing through the entire academy, curious about the source of such a powerful sonic wave, he ventured inside; he knew that it was one of two possibilities, either a beast had found its way inside the monastery, or-

“Bwaaaarp!! Oh my! Excuse me” Said a gentle voice from the shadows, quite the contrast considering the magnitude of the belch erupting from her.

“Mercedes? Is that you?” the blonde man said as he approached a bit more confidently, at least that was until he crashed face-first into a soft wall on the way “Agh” he said taken aback by such an event, he swore the kitchen wall wasn't there.

“My! Your Highness! You do not have to be so rude” said the woman as she turned on the light, a pooty look in her face as she tried to look behind her, something that was becoming increasingly more difficult as of late. It had been a few weeks since the new professor Byleth had enrolled in the academy, while she had been such a gentle soul with all of the Blue Lions, she had taken especial care of Mercedes, inviting her for teas, showering her in gifts, and most importantly, drowning her in sweets; Mercedes had always had a terrible sweet tooth, something quite apparent with the fact that whenever she wasn't eating them, she was baking them, and as such, she just couldn't say no to the teacher's offering.

At first, it started harmless enough, just a few candy bars here and there, but as time went on, they only got larger and more frequent; cake, pies, ice cream, a jar of sweets, all in just one date! The results were obvious, Mercedes hated physical activities, and as such, the pounds piled on and on and on; but not only that, she grew ever so glutton, craving more and more sugar, always carrying a backpack filled to the brim with chocolates and pastries, at the end of the day she always cleared the entire thing.

“My dear lord, Mercedes, I've told you that you can't sneak here at night, this is the third time this week you've let this place empty of sugar... Wait, are those the bags of sweets the merchants brought today?”

Mercedes blushed as she looked around her, everywhere she saw, there were just empty wrappings of sweets, at least two entire bags, all packed inside her bulbous stomach and mountainous behind, for some reason, the gentle woman derriere had taken the brunt of her gain, making her twin cheeks couch-filling yoga balls of pure lard, it was such a blessing that she was able to use her healing magic from afar, because right now she could barely move a step every minute, it honestly impressive how out of shape she was “I just couldn't help myself, I only came here for a few slices of cake, and when I saw the bags I just couldn't control myself”

“Those sweets were to commemorate the rebirth of the goddess!-sigh- You leave me no choice Mercedes, you've gone too far, from now on you will be on a strict regimen of diet and exercise”

“Exercise?! Your Highness, you can't force me to do such awful things, you know I can't handle physical work”

“Mercedes, you've done this to yourself, look, I'm doing this for you own good, it is my order”
...............

“Huff-Puff-Huff” Today was the start of the blob-like woman new regimen, despite her constant pleas, and thanks to the combined force of must of the class, she was finally taken to the training area. Taking pity on her state, the future king went easy on her, giving her the lightest dumb-bells he could find, yet even those proved too much for the unfit woman, as even lifting her arms felt like a workout form hell.

“Mercie, you don't look too good” Said Annette, Mercedes best friend, as she went to check on her, while she also shared her love for sweets, even she had to admit that Mercie had taken it to a new level, yet she couldn't bring herself to say such a thing.

“Dimitri said the same-huff- thing, I told him I hate exercises, but her forced me-puff- to do it after I ate two bags of candy” The blond woman said almost fainting, her face pale and covered in sweat “Burrrrp, oh Annie, please excuse me” she gathered enough strength to mutter her words, but it seemed she didn't have enough left in her to be embarrassed.

“Oh dear, I'll go get professor Manuela, you just stay here” Annette murthered as she rushed to find the priestesses. And as she was leaving the door, a woman of green hair entered the place, in each hand an entire cake.

“Oh-huff-Professor... How shameful that you have to see me this way... I couldn't convince Dimitri to let me go... Oh dear no! Don't even joke about that... Y-you brought me some snacks? I really shouldn't, Dimitri ordered me to-... I suppose you're right, this should give me some strength... W-what?! You want me to pretend I exercise so you can instead bring me sweets?... I suppose that wouldn't be so bad” Mercedes was weak when it came to self-control, at the first sight of the cakes she wanted nothing more than to dive headfirst into them, something that Byleth was more than happy to help her with, cramming a massive slice in her mouth as she rubbed her obese body with love and care, it seemed like this diet of hers was going to have much different effect than expected.