Rubber Dick (Patreon)

This image was clearly never intended to be realistically manipulated, but at least it gave me an idea.

I quickly glanced away but I had pressed my luck too many times. He was clearly aware that I was checking him out, over and over. Once or twice perhaps isn't a big deal. Doing cardio is boring and the gaze is drawn to whatever is moving, but he'd figured out mine was drawn to his moving body all the time. What's worse he slowly got out of the machine I had no idea what it was called, or how to use properly, and was making his way toward me on the elliptical.

No reason to look away now I guess. I'm not out of shape. About normal for someone who eats in moderation but without counting macros, and as muscled as someone could be who goes to the gym between no and two times a week. No gut, but certainly no washboard.

This guy on the other hand had shoulders close to twice my size, and on his way toward me he peeled off his tank top to reveal abs that looked defined without him even flexing them.

"Hey, man. You want a closer look?" This was mortifying, but I thought honesty was the way to go. "Sorry, but yeah I do. I can't imagine the work that goes into maintaining a body like yours." He was standing right in front of me, radiating heat from his workout. "How close would you like to get?" he asked, leaning slightly toward the elliptical. Was he hitting on me? Let's not play any games in the off chance he was. "Honestly, I would mind you inside of me." He removed his baseball cap and put it back on again backward. "Thought you'd say that. Why don't you wait in the yoga room and I'll go and grab some rubber?" I don't remember what affirmative I grunted, but I was off the elliptical in a second and over in the yoga studio just a few more.

It was empty for the day and the lights were off. No one would disturb us. I flicked the light switch and absentmindedly looked at the neatly piled mats in the corner of the room while I kept running scenarios in my head. This was a prank and he wouldn't show up. He was offended and he with all his mates would beat me up. He and all his mates would show up for a gang bang. After what felt like an eternity he showed up alone, looking as when he'd left me, bare chest and sweatpants. He closed and locked the door behind him and asked me "Still not naked?" with a smirk. I quickly peeled off my T-shirt, kicked off my shoes, and then in the corner of my eye saw something not right.

As I turned to him he was blowing up a long, pink balloon. The kind you could twist balloon animals from, perhaps. I've never made one myself. He looked and me and took a pause in blowing into the rubber. "Oh, I never said anything about sex. This will be just as mindblowing to you. I promise." Not sure what he meant, I went back to pulling off my clothes, socks, shorts, and boxers.

"Get up on that instructor's block," he said, tying the end of the ballon. There was a block of fairly rigid foam next to the mats that I had never seen anyone use. I moved it a bit closer to him and then with some hesitation faced away from it, put my hands on it, and jumped up to a seated position. I now faced him, and watched him rubbing something over the balloon, like lube or something. He must have squirted some on the balloon while I was moving the block. "That's not going to work", I told him.

"Let me worry about that," he said, moved behind me, and started to rub my asshole in a circle. Then he started to dip into it, just a little at first, but then more and more until he was basically fucking my with his finger. Then he added another finger, and twisted his way out on every stroke.

Then there was a pause followed by something larger pushing against my hole, but to my surprise I could feel it slip in with just a bit of resistance. It went about as deep as his fingers had gone until he made a little pause. Then came a twist of the balloon in my ass, and he pushed again followed by a little twist in the other direction.

"Aaa! Fuck!" I let out, unable to control myself. "You like that, balloon boy?" he said with his bass voice reverberating just behind my head, and flicked the balloon with his finger, sending the vibrations straight into my prostate. "Fuck, yeah." It was the best sensation I'd had in a long time. It was filling me up unlike anything I've felt before, but without being painful. Well, not too painful at least. It was in that weird range of pain where it somehow added to the arousal.

He worked the ballon again, but slower. Maybe in half an inch, rotate about an inch, in another half an inch, rotate back an inch. Perhaps. What did I know? I was facing the other direction, and wasn't really paying much attention to anything but the constant friction against my prostate and my ever filling intestine. I realized I was sounding like a barn animal, but given how good this felt I didn't care, and obviously neither did he.

He paused and asked "How does it feel to have your ass pumped full?" The balloon must have curved inside and followed the intestine, because I could feel it all the way up to my lungs. My guts obviously felt bloated as well, but the most significant feeling was that of having my ass completely full and distended. "It's the most amazing I've felt in months. Longer even."

"That's good, because the magic trick isn't quite over yet." He stepped closer again. "What do you mean?"
"Let's just say you won't have problems with XXL cocks," and I could both hear the balloon pop and feel a sharp reverberation travel up my guts. But after that I felt just as full as before. "It'll come down again to normal size in a week or two, but you'll always be looser."

He was starting to leave the room while I was still having trouble comprehending what was happening. I tried to move, but there was that feeling of having a foot or two of balloon animals up my butt.  "Hey! What just happened?"

"Let's just say if I or my friends need some relief we know where to go. In the meantime you should get a comfortable butt plug."