Yuna was, of course, very shy about this whole thing.

She turned around so her pale, smooth butt was facing against your miniscule body, and bent herself over slightly, reaching for one of her cheeks and tugging it so it pulled back away and revealed her rear entrance to you. Tight and waiting. 

If this had been Paine, or even Rikku in a bad mood, she might have shoved you up there with force, giving you no real say in the matter whether you wanted to or not.

However, Yuna was gentle enough to not want to hurt you. She let you be the one who decided how you wanted to do things. 

“You…want to go…in there?” she asked, and looked over her shoulder at you with a deeply flushed face, baffled. However, you were quick to wave your hands in a bit of a panic and try to explain to her before she got ahead of herself and did something which might turn out…not so good for you.

“Not in there, Yuna. I mean…just…just let me take charge.”

Now it was your turn to flush. You were feeling shy about it all of a sudden. The idea of taking charge of her body, it was kind of funny, considering she was a literal giant compared to you. But you looked up into her massive eyes and tried to give her a softly reassuring smile.

“Just bend over a little more for me…”

She did so, and you looked up in some awe either side of you, at her milky cheeks, her massive butt which basically dwarfed your tiny body by comparison. 

You realized that if she wanted to, she could shove you in there anyway against your will. Thankfully she didn’t though, and you were able to have some actual, proper fun for once. Walking right up to her tight hole, you planted your hands on the surface of it, and pushed your tip inside, treating it like she was normal-sized, almost.

Yuna let out a sharp gasp of shock when she felt it. You may have been tiny, but it still brought her a pang of pleasure, so much so that her hand almost slipped off of one of her cheeks, nearly letting it slam against the other one. Thankfully she caught it in her grip again before it could, and you shuddered, feeling relieved.

Getting back to it, you began thrusting into her, while Yuna closed her eyes and jolted with pleasure, her back arching inward, her butt pushing outward. She couldn’t believe that even from such a tiny body, she was able to feel so much.

Eventually you finished inside of her, and pulled back out of her rear with a pop, falling clumsily against the surface of the desk, covered in some of the results of your efforts. You shook your head, a little sweaty and flustered, and looked up at Yuna. 

She looked back around at you again, even more pink than before. She bit her lip, and then you watched, as one of her slender digits slid up smoothly over her mound from the front of her body, curling over her skin and pressing against her tender slit.

“C-can you do it here next?”

You eyed her pussy, and cracked a little smirk at the corner of your lips. 

“...Sure I can.”

Yuna smiled shakily, and excitedly, and she used two of her digits to push against the inside of her lips and guide them apart. Her massive, musky passage spread itself for you like her legs might have if she were normal sized, or at least as small as you were.

You walked up towards the waiting entrance, swallowing thickly and tensely, wondering if you were really prepared for this. Her pussy was so much bigger than her asshole, she actually wouldn’t have to really try to swallow you up inside it, intentionally or otherwise.

You reached out with both your hands and pushed one against the rubbery nub of her clit, using a fair amount of effort, relatively, to twiddle it and push it in circles. Your other arm pushed inside of her slit and thrust deeper and deeper than before, wiggling around a little bit to see if you could provoke a reaction from her, and you certainly did. Your dick would be doing the work next. 

Her walls throbbed around you and became slicker and slicker with her own fluids the more you pleasured her like that, and so you pushed in and out even more rapidly, wanting to reach as deeply as your little arm would be able to manage. 

And you did manage. 

“Ah~!” Yuna gasped as she felt your limb entering her. Her walls vibrated around your limb, throbbing readily. Suddenly, even though she knew it was a little bit naughty of her, she wanted to wrap her hand around your body, grip you tight, and shove you up inside of her, keeping you there for good.

Suddenly, that seemed like the best thing she could imagine. Yuna couldn’t help herself.

She was always so nice, she was always so good. She behaved, she was kind, she never did anything that put anyone else in danger, even though she had been put in danger so many times. 

So was it really so wrong for her to want to…do something a little bit bad for once?

As soon as she pinched you by your waist, you should have known. As soon as you watched her spreading her pussy far wider than you needed for your tiny dick, you should have anticipated it. But you supposed it seemed so unlikely to you that Yuna would ever hurt you, that you didn’t worry about anything like that.

You just kept thrusting, right up until the moment when she wrapped her hand around you far tighter than normal. That was the moment when you should have known. 

But you kept trusting.

That was how you ended up being thrust up inside her, body and all, jammed into her vagina like you were nothing but a dildo, and that was where Yuna began to keep you.

Forget going back to the surface world. Forget the possibility of ever becoming normal again.

This was going to be your life now.

Nothing but a sex toy for the sweetest girl on the Celsius.