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“Oh, Steve,” Tony sang as he came in the door. “I’ve got a surprise for you.”
“Nope, no surprises.” Steve said from the living room. He didn’t take his eyes off of the drawing he was working on.
“Oh come on, at least hear me out.”
“Tony…”
“Listen I had this idea-“ Tony sat on the arm of the recliner Steve was sitting in.
“If it’s got you singing my name like that then I’m sure it’s a bad idea.”
Tony took the pencil and sketchpad from Steve’s hands and placed them on the coffee table. “I was still working on that,” Steve protested lightly. He smiled and pecked Tony’s lips. “Alright, spit it out.”
“Coke and mentos.”
“Coke and mentos?”
“I saw a video the other day of someone swallowing a bunch of mentos and then downing a two-liter of Diet Coke to bloat up their belly. And honestly it was really hot so I decided you’re going to give it a try.”
“Am I, now?” Steve raised his eyebrows.
“Yep. I already got the supplies: three sleeves of mentos and six liters of soda.”
“Six?!”
“Well I figured with all your superhumanness or whatever you’d be able to take more than an average human. I mean just think of how much food it took to finally get this tubby little belly of yours.”
“I don’t know, Tony. You know what carbonation does to my stomach. That much soda and I’ll be gassy for a week.”
“Exactly.” Tony pulled Steve’s shirt down slightly and peppered kisses along Steve’s collarbone. “So what do you say? You in?”
For as hard a time as Steve always gave Tony when it came to these little challenges of his, Steve always agreed. He loved stuffing himself and packing away calories. Now, slowly but surely it was starting to show.
He was by no means fat—not yet anyway—but three months of him gorging himself on the seemingly endless food Tony brought and fed him had given him a “dad bod” as Tony affectionally called it.
Combatting his metabolism was tough, but the more he ate, the more it struggled to keep up and Steve was thrilled he now had a small rounded out belly and slight love handles to show for it.
“Alright, you horny bastard.”
“Good. I’ll be right back.” He raced off to the kitchen. “Get comfortable!” He called back to Steve.
Steve knew he should probably replace his too-small jeans with a comfortable pair of sweatpants, but the thought of his belt and waistband cutting into him more and more as his stomach inflated with liquid and air had his dick twitching. So instead he just leaned back and settled further into the chair.
“Okay, so from my research, it looks like the best way to do this is to crack the mento with your teeth, swallow it down with some water, and then start chugging.”
“Was your research just watching porn?”
“That was part of it, yes.” Tony handed Steve three mentos and a bottle of Diet Coke. “I wanna make sure you get as big as possible so we gotta do it right. Now, drink up.”
Steve popped all three mints in his mouth and did as he was told. He chugged about a quarter of the bottle before coming up for air. He sat for a second waiting for something to happen but he didn’t feel anything other than the liquid entering his stomach. He let out a small burp. “Tony, I don’t think it’s- oh.” Steve felt something expand in his stomach as the reaction started to happen. He placed a hand on his belly and was surprised to feel it already bloating slightly. Then a huge airy burp forced its way up his throat and out of his mouth, the gas desperate to escape. It startled Steve and he clamped a hand over his mouth.
Tony chuckled. “What were you saying about it not working?”
“Give me some more.”
Tony handed Steve some more mentos and he repeated the process. It was certainly working. The mentos were reacting so strongly to the soda that Steve was having a hard time swallowing with all the burps coming back up.
Steve finished the first bottle and sleeve quickly and found that even after a few minutes his stomach still felt like it was expanding. Steve was already pretty big and they still had two more bottles planned.
“Fuck.” Steve shook his bloated belly. He could hear all the soda sloshing around. Another airy burp rushed past his lips. He was so turned on right now.
“I wasn’t expecting this to work so well so quickly,” Tony’s fingers traced circles on Steve’s distended belly.
“I told you my stomach doesn’t like carbonation.” He burped again. “God, I can’t stop burping.”
Just to taunt him, Tony pressed on his stomach forcing more gas out. “I’d say this little experiment was a success.”
“We’re not done yet.”
“You want more? Steve you’re already huge!”
“Well, I don’t feel full, just stretched, which means I must have more room. Plus, all this burping is freeing up space.”
“Fuck, Steve.” Tony loved when Steve got like this; so determined to get bigger. “You’re gonna be so gassy tonight, babe. Your belly is gonna be so angry with you.”
Steve pouted, “I might need your help getting all that gas outta me, doll. I don’t want my tummy to be upset all night.”
Tony smiled and handed Steve a new roll of mentos, kissing his knuckles. “Don’t you worry, baby. I’ll help get your tummy to settle.”
Tony moved from his perch on the armrest to straddle Steve’s lap. When he leaned in to kiss him, he could feel Steve’s rounded belly against his own, slimmer abdomen. The sensation made him shiver and he ground down into Steve to let him know just how hot he found this.
He rested both his hands on Steve’s stretched sides. “Keep going. I want to feel you grow.”
Steve smirked and decided to go big. He popped half the roll of mentos in his mouth and followed it by chugging 3/4 of the new bottle. When his lips popped off the tip of the bottle gas immediately poured out of him. Burp after burp in rapid succession and there was nothing he could do to control it. A particularly forceful burp brought foam up the back of his throat and he clamped his mouth shut, burping softly through close lips.
“Jesus,” Steve said when he was finally able to breathe again.
“Too much, too fast?”
“I think so. I didn’t give my stomach enough time to stretch and now it’s cramp- ow!” He reached down to massage the offending muscle.
“Here, let me.” Tony moved Steve’s hand aside and he began to apply light pressure where Steve’s belly felt especially tight.
Steve leaned his head back against the chair trying to relax as his belly continued to grow. The more Tony massaged, the more Steve’s stomach burbled and soon he could feel all the trapped air moving through his intestines and filling out his lower belly. Steve shifted slightly and slid his hips forward before releasing a loud bubbly fart. Tony felt is come up between Steve’s legs and vibrate against his dick. It was a new feeling, but holy shit it almost made him come on the spot.
“Fuck, Stevie. You keep doing that and I’m not gonna be able to control myself.”
“God, there’s so much more inside me. I’m gonna be doing that all night.” Steve sat up and reached forward grabbing Tony by the hair and pulling him close. “You’d like that wouldn’t you, doll? To spoon me while I fart right up against your dick? To rub my belly and feel how big I’m getting? To coax up more burps and tell me what a pig I am? Would that turn you on?”
Tony felt breathless. “Finish the bottle,” he gasped.
Steve took in the rest of the mentos and started drinking, slower this time. He definitely felt overfull and all the sugar was starting to upset his stomach. While he drank, Tony kissed and licked down Steve’s throat feeling him swallow. “You’re doing so good, Stevie.” Steve paused and belched against Tony’s ear. At this point Tony’s poor leaking dick was fighting a losing battle in his pants, especially now that Steve farts had become more regular.
By the time Steve finished bottle number two, he was panting. His inflated stomach was now pressing against his lungs. He tossed the bottle aside and let out a groan. “Oh, fuck. Ow.”
“I’m so proud of you, Stevie. You did so good for me today.”
“Just give me a minute,” Steve huffed out. “I can do the last bottle.”
“Steve, baby, you’re going to hurt yourself.”
“Superhuman, remember?”
“Yes, but superhuman is still somewhat human and the remnants of that pre-serum sensitive stomach of yours can’t be feeling too hot right now.”
“Nothing I can’t handle.”
In reality though Steve’s stomach was churning. Between the gas and the liquid there wasn’t really any space in his stomach and the loud angry gurgles were making that fact known. Still, Steve could rival Tony when it came to stubbornness and it was rare he backed down from a challenge, especially when that challenge was turning him on as much as it was. “Undo my belt and my jeans. I need more room.”
The second his stomach was no longer constricted it ballooned forward. Gas came out of both ends as his entire stomach shifted. At the same time he came with full force screaming at the overstimulation.
“Fuck, I needed that.”
“Which part?” Tony teased.
“All of it.” Steve wore a dazed smile. “Now I’m ready for more.”
“Steve your stomach is absolutely huge. It’s bigger than it’s ever been. It’s okay to stop.”
“I still got room to be bigger,” he insisted. “Now give me the bottle.”
Tony learned long ago in their relationship that Steve often needed to learn things the hard way.
“Well then, let’s see how much more you can take, tubby.”
Steve took one mento at a time now and chased them with small mouthfuls of soda rather than large gulps. But it was evident from the start he wasn’t going to be able to finish. He’d barely finished 1/3 of the bottle before he started choking on his swallows, nearly gagging a couple of times.
Tony gently pulled the bottle from his hands and capped it. “At ease, soldier,” he whispered. He grazed his knuckles along Steve’s taut belly, taking care not to push. “How’re you feeling?”
Steve let up a calculated belch. “A little sick,” Steve admitted. “But mostly huge. And so, so horny.”
And that was certainly apparent. Tony could see Steve’s dick already perking back up in his briefs.
“I didn’t finish,” he mumbled sadly.
“We’ll build up to it,” Tony assured.
“I can’t move.” Steve groaned and cradled his stomach. He pushed out two long, bubbling farts. “God, I’m massive.”
“And you’re only gonna get bigger.” Tony promised. “You’re gonna get so big you won’t be able to get up off the couch. You’re just gonna lounge around eating all day and creaming in your pants.”
Steve pulled Tony in and kissed him deeply. He slipped his tongue into Tony’s mouth and Tony could faintly taste the artificial sweetness of the soda. Tony caressed Steve’s stomach as they made out, getting it to settle slightly. The result was even more gas pouring out of him. Steve tried his best to pull away when he could and burp into Tony’s ear or into his hair but in a moment of passion an unrestrained burp came up right against Tony’s lips. Tony moaned and kissed Steve harder.
“Of course you’re into that,” Steve chuckled.
“What can I say,” Tony replied absently. “You too full for me to ride you?”
As much as Steve wanted Tony to fuck him senseless right now, he wasn’t confident all that jostling would work out in his favor. “Belly rubs first, sex later.”
“Want me to deal with this for you?” Tony brushed Steve’s dick. Steve nodded, and Tony pulled him from his boxers.
Steve was far too sensitive to last long and soon he was coming down Tony’s throat. Tony swallowed Steve expertly, fondling his balls as he came. With Steve spent, Tony had one more thing to take care of. He pulled himself out and began tugging roughly. Just as he was about to orgasm, Steve grabbed his wrist.
“Come on my belly.”
“Holy shit.” Four more tugs and Tony spilled all over Steve’s massive stomach. He rested against Steve’s side for a moment before grabbing a couple of tissues from the coffee table and cleaning up. Then he melted against Steve, nuzzling his neck.
His hands returned to Steve’s belly which had finally stopped stretching. With slowly increasing pressure Tony resumed his massages, coaxing more gas out of Steve’s troubled tummy. The next hour was filled with gaseous cuddles, as Steve’s stomach slowly deflated.
And just when Tony thought they were both going to drift off to sleep, Steve brushed his fingers along Tony’s jawline.
“I’m ready to finish the bottle.”