Different Kind of Boss
It took quite a bit of effort, but with one last attack, you successfully knockout the boss of this dungeon. This place wouldn't normally cause so much of a hassle for you, but whoever told you about this place seemed to forget to mention how the area was filled to the brim with poisonous enemies. This left you lacking the necessary amount of antidotes you clearly needed. Nevertheless, you have made your way to the end, eager to open the treasure chest. The chamber its in seems darker than the rest of the dungeon but nothing you're not familiar with.
As you open the lid to the box, however, the most mortifying thing you can find after such a painful quest rests inside the chest: nothing. With a heavy sigh, you decide to make your leave as to not succumb to your wounds. A playful giggling from the ceiling causes you to hesitate. As you look up to see the source, you realize how tall this specific room seems to go, though one could have chalked that up to the lack of light. Within the darkness you can make out the outline of an assortment of shapes floating around. 3 triangles in particular seem to lean down from the darkness, revealing themselves in a formation akin to a smile, the bottom triangle begins to speak.

"Heya, didn't realize anyone else was gonna be here but I will say that its impressive a being of your stature could overcome such a place. Good job on that!" The triangles tilt to the side as a pair of pie-shapped pieces float down next to it and seem to start clapping. It doesn't sound very celebratory, though. The being's tone sounded synonymous to one may use when praising a pet, and the 'hands' clapping sounded less like applause and more like 2 small plastic cups being dropped repeatedly. This situation stirs a lot of confusion in you, but you do notice a wrapped up box tied to one of the hands. You suspect it to be the original contents of the chest as it is wrapped in several ribbons.
"Yeah, I sneaked my way through here for the chest. A friend's birthday is coming up and I wanted to get them something. They have a peculiar taste but I do aim to please those creatures I enjoy." says the being, dangling the box by one of its ribbons. You feel the poison eat away more at your health. You really don't wanna deal with whatever nonesense this thing above you is spewing and you feel like you don't have the time to either. You kindly request if you can have the box or at least trade something for it. The being holds one of its hands up to its 'chin' to think.
"Hmmmm, I want this treasure for my friend, though. However..." the being closes its 2 triangular eyes for a moment before re-opening them to squint are you closely, their mouth bending in a mischevious way.
"This situation is rather uncommon for me, too. It would be a shame for me to pass up an oppertunity to play with a new toy. I will give this treasure up to if you let me play with you however I want for 1 hour. Deal~?" The being offers one of their pie-hands out for a shake.
The one word that was at the forefront of you mind right after they spoke was 'no', and your mouth probably was going to shout that out if your wounds weren't catching up to you. You clutch your stomach in pain as you focus on not passing out.
The being's face leans closer to you, appearing even more smug.
"If it sweetens the deal at all, I do make sure to take good care of my toys. I am very gentle with my playtime, at least for the most part." it says, tilting its face to the side in an innocent manner.
Given the circumstances, you conclude that taking this thing's offer is your best bet, as declining it probably leads to you passing out in this toxic dungeon full of monsters. You reluctantly place you hand atop their's, feeling its plastic-like texture. The traingle eyes widen.
"Splendid! Once I'm finished with my playtime, I'll send you on your merry way with the treasure I've procurred.". As the being says that, the remaining shapes from above float down, spinning around to take a peculiar form in front of you.
"You may call me 'GAT', by the way. Just in case you need a name to moan during our hang out~."

That last part sets off more alarms in your head. You go to raise a finger to protest but before any words can escape your mouth, a ribbon strand shoots out from the open side of one of GAT's hands, wrapping around your waist and binding your arms to your sides. The ribbon then yanks itself back, but instead of propelling yourself quickly towards the being's pointy-looking chest, you begin to float gently towards it as if you were in space. GAT then cups your chest with its other hand. The feeling isn't painful but you certainly feel as small as a toy, despite it's grasp being the one that feels like sturdy plastic.
GAT leans its triangular head down to present an orb of various colors in front of you. Its colors are ever-shifting, and with how hard it is to see anything that isn't comprising the entity right now, it makes for a beautiful place to rest your eyes. It looks very clean, like a freshly polished pearl. You could probably fall into a trance just observing it had GAT not just pressed it suddenly into your face. Its not painful, but it does feel odd to have a giant gem-like object resting on your face. Its not pressing hard into you, but GAT is making sure theres no space between you and the colorful orb.
"Lemme clean your statuses first. Wouldn't want my playmate passing out on me, especially for our first time!" GAT says, rolling the orb between your left and right cheek. Back and forth the pearl rolls, each pass over your eyes makes you feel more at ease, more relieved as you feel any traces of toxin in you fade away.
"Hmm hmm, you look really adorable like this, especially with that face you got." GAT chuckles, giving the orb a few more rolls over your face before retracting it back above its head. You certainly feel healthier but you find yourself to be nervous, your rejuvinated mind still worrying over where this forfeited time with this entity will lead. The ribbon binding your arms seems to have tied itself around you now. As you float parallel to GAT's chest-piece, 2 more ribbons emerge from each of it's hands: one beginning to wrap your chest as the other binds your feet together. Looking down you can also see GAT's large 10-sided-dice-shaped bottom slowly sway side to side. Given the floating feeling and how secure your body felt from the ribbons, the show of GAT's largest shape gently moving about is proving to be a delightful spot for your eyes to lay upon.
"Well, I WAS gonna save it for when you were fully wrapped, but if you're gonna eagerly stare at it-" GAT states, laying your body onto your back, using one of its hands as a platform as it floats above you, one of the flat parts of the dice facing you.

It may have grown in size in the next few seconds, its hard to tell with it suddenly taking up most of your vision."-I guess I'll sandwich you with it now!" it finishes, as the large shape is quickly pressed against your whole body. Its not as solid as GAT's hands, it does seem to squish a bit around you, almost like a water bed, but its certainly sturdy.
The shape gently rolls all over your front side. 1 side of this dice can hold your whole body so feeling its squishy form grind against you feels, good? Despite seeing lots of peculiar things in your day, having a giant soft dice grind against your entire body feels strange, both in a literal sense and a social sense. For once you are grateful to be alone and at the mercy of a monster deep within a dungeon, as no one can judge your silly predicament. The oddly soft texture is taking its time with you, switching sides on occasion as if to make sure each of its sides gets the full experience of rubbing and bouncing on you. Theres not much you can do about it, too. Even if the dice wasn't so large and your limbs weren't bound together, you did somewhat agree to this. Between the time the dice was changing to another side, you noticed that GAT has positioned its head and face to look right at your face, its triangles assorted in an arrangement of adoration.
"Gosh, seeing your pressed form, FEELING every bit of you, its amazing~." GAT sighs. A hint of embarassment comes to mind but its quickly replaced by another sudden feeling of confusion. The hand holding you up flips you around before the dice squishes upon you again, now getting a feel of your entire backside.
"Mmmmm, feeling around new toys is wonderful!" GAT gasps, "Though its hard to beat seeing their adorable faces.". The delayed wave of embarassment reaches your face. Were you blushing? Were you truely enjoying how this thing was treating you, or does this bizarre experience come off as deplorable to you? Regardless of how you truly felt or not, your face must've changed to a significant degree, as it's motivated GAT to press, grind, and bounce the dice particularly deeper into your backside. Each side getting a turn. Each movement along your form feeling so squishy and soft, yet feeling a bit taxing on your energy. Each press after the first has been getting more intense. The fact this entity's face was upside down did not confuse the fact it's expression was one of arousal. They must have been getting a bit impatiant with only pressing the dice against you, as they soon decided to grab you like a crane would its prize and press you more into each side. GAT made sure to meet your face and rear with each side of the 10 sided shape at least once. They may have repeated the actions on some of the sides, they weren't keeping too much track. You weren't either. To you, each side looked the same and feeling your face pushed so deep into it would disorient you more than the last side. When the hand finally held you away for a time, you were exhausted again. Whether it was more or less tired than when you beat the original final boss of this place is hard to say, but you were dizzy for sure.
GAT sighs. "Aaahh, that felt amazing. Spent more time with my rump than I expected!". You are too tired to think of a retort as another pair of ribbons begin to snake their way around you. One finishes up wrapping your upper body as the other binds the rest of your legs, squishing your thighs gently together. Only your head now is free of this ribbon bondage. One of GAT's plasticy hands gently presses into your back, bringing you close to their chest. It looks down at you.
"Only a few more minutes now, toy. Once I replenish myself, I'll let you be on your way. I'll even carry you back to the entrance if you want~." GAT says, finishing the last statement with gently pressing its other hand against your cheek. Your mind was in too much of a daze to process exactly what their words meant, but you soon started to realize it. You look up to try to see GAT's face, noticing a smaller triangle float next to it for a moment before floating behind you.

You feel a small shape be gently placed in contact with your back. After a second, you begin to feel your energy waning. In another situation, you'd be able to shake this off with ease, but as you are now, body bound and head in a daze, you are helpless as this entity drains your energy. GAT does gently hold your body with both it's hands aginst a flat side of it's 'chest'. This part feels the most sturdy of each one you've been in contact with. A nice respite from the previous abuse of the soft yet eager dice. The solid force protecting your front and back, you almost feel totally safe. The shape behind you steadily sapping more and more of what little strength you still have. Your face hasn't left GATs, noticing it does appear to be one of comfort. Maybe they know this is tiring and do want you to feel good, or maybe its a facade deployed to ellicit another face out of you for it to admire. In this state, its not like you can do much. There is nothing to tell how much time exactly has passed and your body is too tightly bound to move anything. Accepting this, you lose the desire to move it at all. You let out a sigh, as you decide to close your eyes, the last thing you see is GAT's caring smile.
After some time, you hear a ringing in the distance. You begrudingly open your eyes, feeling the same way one would be as their alarm goes off to wake oneself up for work, but knowing fully well you did not get enough sleep and just want to lay back down. Something is over your eyes and head from what you can tell. You know even early morning fatigue doesn't cause your vision to do this. You try to turn your head to take in the surroundings but can't move too much. You realize its ribbon thats covering your head, as it still is gently hugging the rest of your body. You have no issues breathing, but you're still tired and just wanna lay back down. Before you can make that choice, you barely see the outline of 3 triangles float into your view, a familiar face eminating from them.
"Heya, looks like our hour is up. You did fall asleep so I opted to just bring you out that dungeon. The treasure is all yours, too. Did you wanna get up now?" GAT asks. There isn't any hint of malice behind that voice, at least this time. You try to think about what you want but your body and brain seem to still want to recover, so you close your eyes and ask GAT to hold on a few minutes. You hear a chuckle, feeling a plasticy touch gently rub the top of your head side to side, hearing one more thing before revisiting dreamland:

"D'aww, of course~. You make for such a wonderful toy."