Frisk x Muffet Buttsex (Undertale)

“Oh my, this has all been a big misunderstanding~” Muffet exclaimed, reading the telegram her spider brethren in the RUINS had sent to her. Frisk stood across from her, panting from exhaustion after surviving the arachnid’s relentless assault. He had tried his best to spare the monster, but was close to losing. He was lucky the spiders in the RUINS had sent the telegram when they did. “I thought you were someone that hated spiders! The person who asked for that SOUL…they must have meant a DIFFERENT human in a striped shirt!” She grinned her sickly sweet grin, and Frisk couldn’t help but shiver. Much to his own confusion and frustration, there was something he found oddly attractive about the monster.

“Sorry for all trouble, ahuhuhu~” Muffet covered her mouth with her hand as she giggled, eyes closing in unison. “I’ll make it up to you! You can come back here any time…and for no charge at all…” As she paused, Frisk’s heart thumped in his chest, for reasons he couldn’t quite comprehend. There was something he wanted her to say so desperately, though even he wasn’t sure what it was he wanted to hear. “…I’ll wrap you up and let you play with my pet again! Ahuhuhuhuhuhu! Just kidding, I’ll SPARE you now!”

Before she could do so, however, Frisk spoke up, saying he would rather play with her instead. Muffet looked surprised for a moment before her playful smile returned to her face, giggling once again. “You want to play with me? Ahuhuhu! I couldn’t imagine ever playing with a human! Besides, what kind of games do humans like to play, hmm~?” Not thinking, Frisk stated that humans played the same games as monsters.

Muffet once again wore a surprised expression on her face, this time accompanied by a heavy blush in her cheeks. “W-What!? Y-You can’t be serious! A human and a monster, doing something like that! It sounds so…taboo~” His heart pounding, Frisk smoothly asked her what game she was thinking of, not wanting to look totally oblivious and ruin what could be something amazing. “Ohh, you humans really are cruel…making me say it~” Muffet leaned forward towards Frisk, running her hands over the curves of her body. “I mean THESE types of games! The games where two monsters connect their bodies and have all sorts of fun~”

Muffet spun around on her feet, her dress lifting a bit as it spun with her. Though it was for the briefest of moments, Frisk could see the well-defined curves of a round, pert butt through the spider’s pantaloons. Frisk spoke up, saying that humans played those types of games all the time, and especially liked playing with their behinds, trying his best to contain his laughter. “Behind? You mean…my butt~?” She turned around, lifting her dress and tugging down her pantaloons, revealing just a small sliver of the bare skin of her ass, the rest of her hands forming up on and around the spider’s bum, framing it perfectly.

“To think that humans could be so lewd~ Maybe I should have fed you to my pet after all, ahuhu!” As she giggled, Frisk took a meek step forward, tunnel vision pulling him towards the spider’s ass like a black hole. Muffet stuck a finger out towards him however, waving it back and forth slowly. “Ah! Not so fast, human. Playing with you does sound rather exciting, but…I do still have to raise money for the spiders in the ruins, you know. Not to mention, it also said in that telegram how stingy you are, not donating to our cause once! I can’t…play with you in good conscience unless you help our cause.”

Gesturing over to the side, a spider came forward, carrying a small sign that said, ‘10000G’. “There. I’ll let you play all you want, all you have to do is donate ten thousand gold to our cause. No big deal, right~?” Frisk pressed C, checking how much money he had saved up so far. He only had around two thousand gold and some dog residue. Cursing himself for buying so many cinnamon bunnies and crab apples, he struggled to think of what to say. Watching, Muffet couldn’t help but giggle, covering her mouth with her hand. “Oh, you humans are so cute when you struggle! I suppose I could give you a discount this time…just give me whatever you have, ok~?”

Frisk didn’t hesitate for a second, handing over every piece of gold he had. Putting the money to the side, Muffet flashed him a sultry look. “Mmm…all this talk of playing games has really put me in the mood, you know…I hope you don’t disappoint me, human~” She turned around once again, bending over and thrusting her ass in Frisk’s direction, wiggling it a bit. Wasting no time, he reached out towards her, fingers sinking into the soft flesh, disregarding the fabric that stood between his hands and her ass. Muffet gasped at the sudden contact, trying to keep her anticipation to herself.

Frisk pulled the pantaloons down until they were at Muffet’s shaking knees, grabbing at the now-bare flesh, squeezing hungrily and eliciting a moan from the beautiful spider. Spreading her ass, Frisk almost felt the need to squint as he looked upon Muffet’s pristine ass in all its untouched glory. He thought back, remembering how monsters didn’t have any bathrooms. Which must’ve meant…their asses went unused. His imagination running wild from the sight, Frisk’s DETERMINATION began to grow in his pants, swelling up at an inhuman pace. He thought he could feel the blood draining from his brain for a moment, or perhaps he was just overwhelmed by Muffet’s amazing ass.

Frisk ran his finger over Muffet’s asshole, and she shrieked loudly, her body shaking and tensing up in response. “A-Aahh, w-what are you d-doing, human!? That s-spot isn’t used for anything, you c-can’t just go touching anywhere you want like that~” With a grin, Frisk leaned forward, licking his lips before pressing his tongue against her asshole. With a tremendous moan her knees gave out, collapsing down onto them, her ass still stuck up in the air. Before she could speak again, Frisk kept licking, drilling her asshole with his tongue, doing his best to push the tip inside the virgin hole. Every ministration seemed to down, revive, and down Muffet again, the monster barely even able to gasp and moan before the next shockwave hit her.

When her asshole was glistening with saliva, Frisk leaned back, much to Muffet’s disappointment. “N-No, wait…don’t just stop, that was just starting to feel so…mmnnn~” Frisk didn’t listen however, knowing that she would appreciate what he was about to do. He tugged his pants down, letting them fall around his ankles as his thick, throbbing DETERMINATION finally felt the sweet kiss of fresh air. Muffet looked back at it between her legs, her eyes shooting open as she comprehended what she was looking at. “Ah, t-that thing…it’s not even proportional! I-Is this the power of a human’s SOUL!?”

But before Muffet could even voice her concerns over Frisk’s size, he lunged forward, pressing the tip of his DETERMINATION against her ass, eliciting another wild moan. Luckily for the spider, he had done a very thorough job lubricating her, and with a little effort from both parties, he began to slide his way into her. The tightness was mind-numbing, almost painful, but the pleasure surmounted every other feeling and sensation like a tidal wave. “Y-yesssss~ It’s so big, human…I can barely even think straight~” Frisk met her moans and gasps with grunts of his own as he finally bottomed out, going as far as he could inside her ass. Both hands on her ass and squeezing again, Frisk began to pull back, before thrusting forward once again. Each cycle of motion loosened Muffet up bit by bit, and before long he was plunging in and out of her ass with relatively minimal effort, much to both Frisk and Muffet’s relief.

The initial pain and tightness fading in the wake of carnal pleasure, the two became more vocal as they each began to enjoy the rough anal sex more and more. “That’s it, human…mnnn, harder, please~ Ahh, yes, right there, right….aahh…! D-don’t stop, please…!” Frisk had no plans of stopping of course, even as his thrusts sped up faster and faster, his DETERMINATION throbbing as if it were about to explode. Before long Muffet found herself in a similar position, her body shaking and quivering, as if bracing for something. “H-Human, I can feel it…d-deep inside me…I can’t hold it much longer…you too, r-right? Then don’t hold back…fill me with your éclair!”

Frisk raised an eyebrow at the totally out-of-place euphemism but could only afford to dwell on it for a short moment, lightning shooting up his spine as he reached his limit, screaming out as he released his DETERMINATION inside Muffet’s beautiful ass. She finished at the same time, her entire body seizing up, a high-pitched scream exiting her mouth before she fell back to the ground, totally drained of energy. When he had finally finished Frisk did the same, falling onto his back, not even staying on his feet long enough to pull his pants up, his DETERMINATION all used up.

When Frisk awoke, he was on a bed of soft webbing. As he stood up he gasped, his entire body throbbing with pain, especially his DETERMINATION. He was still with Muffet, who was currently talking with her spider friends about the money they had raised. Noticing that Frisk had awoken, Muffet approached him with a blush, avoiding looking into his eyes for a moment. “Ah, human…that was a fun game, wouldn’t you say~? Ahuhuhu! You must be sure to visit me again sometime…I don’t think I would mind giving a discount again, as long as it’s you~” She leaned forward, pressing a chaste kiss against Frisk’s forehead. He felt his cheeks flush, telling her that he would definitely visit again soon.

As he left, Muffet called out to him, waving. “And make sure to donate to our cause! We’re introducing a new product: Spider Éclairs~!” Frisk grinned and nodded, walking away. Suddenly, he froze in place. He really hoped those éclairs were shaped like actual éclairs.