Long story short: Rarity invited me to join her for a mud bath. We picked a day, booked an appointment, and planned a trip over there. The two of us and Aloe were standing in the room with the tubs.
"Miss Rarity, this one is yours and the other tub is for gentleman."
"Thank you, Aloe," said Rarity.
"No sea veed vrap today, right?"
"Correct." Rarity giggled. "And actually, we'll be sharing a tub."
That was unexpected, but certainly not unwelcome. Aloe did not miss a beat. "Of course, miss Rarity, do you need anysing else or is everysing ready?"
"Well, the drinks are on the table, the candles are lit, the mud is in the tub, I believe it's been heated just to the right temperature, and we certainly know what to do in it."
Did Aloe blush slightly? I waited until Aloe left before I undressed.
The tub was filled with a black substance which smelled of wet earth, small forest ponds, and autumn leaves. I tested it with my left foot. It felt warm and soft. I put my other foot in it as well. It was actually very pleasant. I started to understand why Rarity was so keen to repeat this procedure every week.
"Beautiful, isn't it? Just as I promised," said Rarity.
"Oh yes. But are we both going to fit?" I asked.
"Why yes, of course. Don't worry about that. You are not that bigger than a pony and I know that two ponies do fit. You just lay down and make yourself comfortable. Slowly, I might suggest. Sinking in this bath is delightful."
I held the sides of the tub as I slowly sat down in the mud. The creamy matter offered some resistance, like stirring a pot of custard. The movements were slowed down. The feeling of warm mud oozing between my thighs was right on sensual.
I lay down and slowly sank to my neck, resting my head on a cushion, and felt the heat and weight surrounding me. My every single motion caused the smooth but thick clay slide over me and caress my body.
I raised an arm above the surface. It was covered with a thick layer of clay. I ran my other hand over it. It was like being coated in a forest-scented liquid velvet. I returned both hands under the surface.
Rarity entered the tub, straddled my hips with her rear legs, and lay on the top of me, folding her front hooves on my submerged chest. Her rear hooves were touching the bottom of the tub. The mud reached her cutie marks. Her back and tail were above the surface. Her body was pressing on my member which immediately responded.
"You seem to like it," said Rarity.
She slowly kissed me. I wrapped my arms around her shoulders, smearing the mud over them. She closed her eyes, savouring the feeling. It was beautiful to observe the contrast between her pristine white coat and the dark matter in the tub.
"Do be a dear and put some more mud on me. I can't wait to get really dirty."
She wiggled her flanks which which made her body slide over my member back and forth. The clay was a wonderful lubricant. A gasp left my lips.
I slowly went from her shoulders down and back, covering her body with warm mud. As I was making my way to her cutie marks she purred to my ear: "Darling, this is heavenly. Please do continue."
I was making sure the layer of mud was thick enough so that it didn't cool off fast. Sliding hands over her muddied body felt like sculpting from wet clay but my artwork was alive and getting as aroused as I already was.
I reached her beautiful flanks and massaged her cutie marks until even the little bit of her flanks disappeared under the layer of mud. I slowly moved my hands to her slender rump which always fascinated me by how soft and firm it felt at the same time. Soon it was covered too. Only our heads were showing their original colors.
I rested my hands on her rump. Then one of my hands found its way below her tail, fingers stopping at her rear entrance. She gasped in surprise and flicked her tail. "Is this how you treat your lady?" I froze. "Because your lady likes it very much," she said and kissed me, forcing her tongue into my mouth. As I resumed my caressing, she started grinding her hips against me, giving me a very intimate massage.
My other hand found her labia and went over them, careful enough not to let the mud enter her. She slid one of her front hooves under her, meeting my hand, and started stroking herself.
I took that as a cue that my hand could venture to other parts of her body, while I kept the other occupied in the vicinity of her tail. There was one particular place I had in mind. I returned to her shoulder, renewing the layer of mud on her body along the way. Then I slid my hand towards the back of her neck.
"I will probably spoil your mane but I guess it's going to be worth it," I said.
"If you will do -- what I think you're going to do -- I will forgive you very soon," uttered Rarity between her moans.
My muddy hand found the base of her horn, circling around it. Her horn lit up with magic. I felt a light tingling in my fingers.
"Yes, continue!"
I ran my fingers up and down the horn, feeling the ridges. Then I gripped the horn and held the grip for a bit. Rarity felt being held in place which intensified her arousal. Her hoof got faster and her moans were no longer soft.
I let go, reaching for more mud. I returned to her horn to give her a muddy hand job. She was crying out from pleasure I was giving her. I felt she was close. My hand near her tail intensified the poking of her rear and then it finally penetrated it.
That sent her over the edge. She arched her back and bit her lips in order to supress the final cry which would certainly be heard in the whole building. Her horn let out an intense glow, pushing against my hand, forcing it away. I had to strengthen my grip to compensate.
After a while her body relaxed and she kissed me. I put both my hands on her cutie marks and returned the kiss. She put her front hoof back on my chest. We broke the kiss after a while. "All forgiven and much appreciated, darling," she said softly. "Thirsty," she added. Then she moved the drink from the table using her telekinesis to my and then her lips.
"But you haven't enjoyed yourself fully, have you?" she uttered and wiggled her flanks again, refreshing the attention of my member.
"Well, can't really say I have," I responded and raised my hips a bit to savor the pressure of her body in the heat of the therapeutic mud.
"That's simply not acceptable but it is easy to fix. Relax, darling."
Her horn lit up again. She looked directly in my eyes. I felt as if the mud has gotten alive around my stomach. She used her magic to apply pressure there. Her expression indicated concentration. I felt the pressure shifting and searching until it locked on its target.
In the next minutes I felt a bliss of my life as she was giving me a muddy telekinetic job. (How does one even call this thing?) She increased the pressure and speed, and started grinding her hips slightly against mine, kissing me. I grabbed her plot tightly. I felt her telekinesis on my member, the weight of her body pressing on mine, her lips on my mouth and her tongue in it, the warm velvety embrace of the mud, and the scent of the clay mixed with her fresh sweat; and then I almost passed out from pleasure as I came. I lay there, unable to do anything, trying to catch my breath.
"How did you like your first mud bath, dear?," she asked when we broke the kiss.
"Umm ... wonderful." I said, mainly in order to test whether I could speak again.
"I must say this has been a pleasurable encounter. Sadly, things do not usually tend to get this heated during our sessions with Fluttershy."
"They don't? I mean, usually?" Mental images of Rarity and Fluttershy enjoying each other in a mud bath like this were not going to leave my mind for a while.
Then she slowly rose from the tub. "Shower?"
"Yeah, shower," I said.