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Shouto's troubled thoughts of his boyfriend evaporated when, in the early evening, he entered “Man Jewels”, a small underwear store in the local gayborhood, and saw the hot man behind the counter. Shouto, who was 18, guessed that the man was about ten years his senior, and a lot taller than Shouto's 5'9". Dark green haired and heavily muscled, the man was at least 6'1". Alone in the store, he was wearing a tight black t-shirt that hugged the curves of his bulging biceps and giant chest, tapering down with his thick back muscles into what looked like a tight waist—but Shouto's view was blocked by the counter.
The man's forearms were bunched up as he held his phone up to his face. Muscular forearms always made Shouto wonder if a guy jerked off a lot. He felt embarrassed by the thought and looked away, his eyes falling instead on the lube and condoms for sale at the edge of the counter.
"Hey," the man said in a deep voice, and Shouto looked back to see the man was smiling at him—a full grin, friendly but also a little predatory. The man lowered his phone and Shouto got a glimpse of an instant message, with a photo of what looked like a young man's naked, well-shaped ass. The man thumbed the off-switch and the phone went dark.
"Uh, hi," Shouto said, trying to calm his suddenly churning stomach, a nervous condition he usually only felt when arranging a hookup. Despite his boyfriend Katsuki's permission (never hard to procure), hooking up with other guys always felt a little wrong—and sexier because of that. But I'm not going to hook up with this guy, Shouto told himself. For one thing, he is definitely out of my league. I've been working out lately, but not THAT much.
Shouto nodded at the man and walked past him to look at the racks of underwear, perfect models on all the boxes. The array was confusing, and Shouto was distracted by thoughts of the man behind the counter. Is he still looking at me? He probably flirts with every guy who walks in here, trying to get them to buy more stuff.
Feeling uncomfortable and eager to leave, Shouto grabbed a box of blue briefs from a brand he'd worn before and kept his eyes down as he went back to the counter.
Finally raising his eyes as he handed the box over, he saw the man frowning at his selection.
"Is this pair for you?" the man asked.
"Yes," Shouto said.
The man looked Shouto up and down with a serious expression. "I don't think these are right for you."
Shouto felt annoyed. "They're fine."
The man raised an eyebrow. "Don't you want a pair that will... show you off?"
Shouto wasn't sure what to say. Is he making fun of me?
"Stand back," the man said. "Let me see you."
Shouto hesitated, but then he stepped back, figuring it was the least awkward way to end the conversation quickly. He felt exposed as the man looked him up and down closely. Shouto was wearing an old pair of jeans and a t-shirt that had gotten a little tight due to his recent workouts.
"Looks like you've got a nice body there," the man said. "Although it's hard to tell on the lower half, with those jeans falling off you."
"They're not falling off," Shouto said, irritated. "They're just... a little loose around the waist. I've lost some weight."
The man smirked. "Been on a diet?"
"A lot of cardio," Shouto said.
The man gestured with a finger. "Twirl for me."
Shouto almost said no, but then—again thinking cooperating would be the quickest way out of this encounter—he rolled his eyes and spun around slowly. When he was facing the wall, the man said, "Stop."
Shouto surprised himself by obeying. There was a pause, and he could feel the man's eyes washing over his back, through his clothes.
"A buck like you," the man said, "should have jeans that hug your young ass tight. And underwear that shows it off even better."
Shouto had never been called a "buck." It sounded like something out of a 70s porno. A hot 70s porno, he couldn't help thinking, and his dick twitched.
Feeling uncomfortable, he turned back around and found the man had stepped away from the counter to reach up to a rack of underwear on hangers. The man was wearing tight jeans that hugged his large, muscular butt, and also hung low, showing off the black band of his underwear. He turned and Shouto was suddenly staring at the full, tight crotch of the man's jeans. Is that all cock? Shouto wondered.
"Hey," the man said, smiling his friendly but predatory grin. He held up a set of black briefs on a hanger. "This is the pair for you."
Hesitantly, Shouto took the underwear.
"I'll break the rules and let you try them on," the man said. "The stockroom's right here."
Putting his warm hand on Shouto's back, he steered the younger man to the rear of the store and opened a door that led to a carpeted walk-in closet, mostly empty save for some boxes in the corner and a stool. It was very warmly lit for such a small room.
Shouto felt unsure. This is weird, he thought. And this man is a stranger.
As if on cue, the man said, "I'm Izuku," and held out a large hand.
As Shouto shook it, he was surprised by how hot the man's grip felt—almost burning.
Izuku nodded at the underwear. "I get those might be out of your comfort zone, so take your time. But I know I'm right about them on you."
Shouto felt like he couldn't back out now, so he slowly walked into the storeroom.
"I'll leave the door ajar a little," Izuku said, "so you know I'm not locking you in there."
Shouto nodded, although the thought of being locked in hadn't occurred to him until Izuku mentioned it. Now he felt alarmed. Uneasily, he kicked his shoes off.
"Are these for a special occasion?" Izuku asked from the other side of the door.
"I hope so," Shouto said. "Uh, I mean, they're for my boyfriend." He unbuckled his jeans.
"You're trying to get his attention?" Izuku asked.
"I guess, yeah," Shouto said as he pulled his jeans off, thinking of how long it had been since Katsuki had fucked him. Way too long. Now in just his t-shirt and white briefs, Shouto looked up and saw Izuku staring at him through the crack at the door. "Sorry," the muscular man said, and he walked off.
Shouto's dick jerked up at the thought that Izuku had been watching him, but he also felt exposed and creeped out. And his stomach was still fluttering.
He heard Izuku shuffling around at the front of the store. Wanting whatever was going on to end soon, Shouto quickly pulled off his underwear so he was just in his t-shirt. He took the strange black briefs off the hanger and noticed what seemed like weird straps on them—and not quite enough fabric. Is this a thong?
As he pulled the briefs over his feet, he realized what they really were.
"Hey!" he said. "This underwear is backless!" The briefs had a large, round hole right over where his ass would go. "I can't wear these. I'm not..."
Izuku's voice came from just beyond the door. "They're for your boyfriend, right?"
"Yeah," Shouto said reluctantly.
"He's turned on by sexy underwear?"
"He used to be."
Izuku laughed. "Sounds to me like it's time to get creative. And trust me, those are perfect for showing off your body and exposing your best asset."
"I don't know," Shouto said, but he was beginning to feel foolish bottomless, with the underwear around his ankles.
"Try them," Izuku said, with a low tone of command.
Shouto leaned down and pulled the briefs up. He shifted around, surprised at how easily they fit around his ass—and how he felt almost more naked in them than out of them, with the fabric tight on his hardening dick, but the air cold on his exposed butt cheeks. Uncertainly, he said, "They feel—"
"You have them on?" Izuku interrupted.
"Yeah, but—"
"Let's see." Izuku slipped into the small closet and shut the door behind him.
Shouto held up his hands as if to fend off the older man. "Wait, I—"
"There's no mirror," Izuku said. "All you've got here is my opinion. I promise to be honest."
"Uh... OK," Shouto said, wondering how he'd gotten into this. He lowered his hands.
Izuku crossed his arms, making his biceps bulge. "You'll need to take your shirt off for me to really see them."
Shouto felt very conscious of his sped-up breathing as he considered his options. It seemed like his only choice was to do what Izuku said, even though that meant he'd be almost naked with this stranger. This hot, muscular stranger, he couldn't help thinking. Slowly, Shouto lifted his t-shirt up and off, feeling the cool air over his thin body. He was aware that his dick was obviously stiffening.
Izuku smiled. "Very nice." He gestured. "Now twirl."
Thinking, I'm just going to do what he says, Shouto turned around so that his bare ass was facing the older man. He stood there nervously, his dick hardening further as he realized he wanted Izuku to like what he was seeing. Shouto felt like what he was doing was wrong, like he'd somehow been tricked into this compromising situation. And where is this going? The older man said nothing, making Shouto feel exposed and confused.
Finally, Izuku asked, "How will you show these off to your boyfriend?"
Shouto forced himself to think about Katsuki. "He'll probably be on the phone with work, pacing, because he's always doing that. So when I want to go to bed, I'll put these on and walk out and see if he notices."
"He'd have to look at you from behind to really see what I'm seeing," Izuku said. "How would you want him to react?"
I doubt he will react, Shouto thought. Katsuki doesn't seem to care about me much at all lately...
Izuku said, right behind Shouto, "You'd want him to do this, wouldn't you?" And Shouto felt the muscular man's hand, hot against his skin, sliding over the hole in his underwear, across his exposed ass.
Shouto jumped. "Hey!"
"You want to be sexy in these, don't you?" Izuku whispered, his mouth right up to Shouto's ear. His hand tightened, squeezing Shouto's cheeks. "You really are. Your ass looks perfect. It makes me want to..." Instead of finishing the sentence, Izuku slid his other arm around Shouto, holding the younger man in place, rubbing his hand from Shouto's stomach up to his chest, pinching one of his nipples. Izuku pressed his warm, clothed body against Shouto's side.
Shouto gasped, his dick now hardening all the way, his body reacting to all the different places Izuku was touching him, but especially to the hand on his ass, where a finger was sliding in between his cheeks. "But," Shouto said, thinking of where they were, of how quickly this was all happening, "but..."
Izuku kissed Shouto's neck, and said, "Don't worry, I've closed up shop for the day. It's just us." He leaned away and pulled his shirt off. Then he pressed against Shouto's side again, skin to skin, his chest feeling so warm it made Shouto gasp.
Izuku's whole hand was now sliding into the crack of Shouto's ass. Shouto closed his eyes and tried to think of Katsuki, but all he saw was Izuku's incredibly hot body, the naked chest he'd just glimpsed, massive pecs covered. He could feel it naked against him, the large, heavy muscles pressing against his upper arm and shoulder. He arched his back without meaning to, pressing his hole against Izuku's large, searching hand.
"But..." he managed to say.
"What, you've never fucked around on your boyfriend?" Izuku whispered in Shouto's ear.
"Yes," Shouto admitted. "But I'm supposed to ask permission..."
"You can't even get him to notice you," Izuku said, and his finger found its target, his fingertip brushing against Shouto's sensitive asshole. Shouto gasped and quivered, his hips bucking slightly.
"It's been a long time," Izuku said. "Hasn't it?"
"Yes," Shouto whispered. It's been months, he thought.
Izuku began to tap his finger against Shouto's hole, off and on, off and on, pressing harder each time, while his other arm held Shouto against him, and Shouto felt, against his hips, something very large stirring in the older man's jeans.
"You need me to warm you up for him," Izuku said. "We'll leave your new underwear on. This will just be about me loosening you up for your boyfriend. Doing him a favor."
Shouto couldn't help bucking his hips harder against Izuku's hand, wishing that he could take the underwear off so his cock wouldn't feel so tight. It was straining against the briefs. Even more than that, he wanted Izuku to push his finger and then his cock deep into Shouto's ass. But I shouldn't want that, he thought. We shouldn't do that.
"This is wrong," he said, and then he gasped as Izuku's finger on his hole grew more insistent.
"You won't come," Izuku said. "I'll just warm you up, get you nice and ready for your boyfriend. You'll be so in heat, he'll love it. We're doing him a favor."
Shouto couldn't think straight. Without meaning to, he whispered, "Yes."
Izuku suddenly pulled away from Shouto, slapping the boy's ass as he stepped back.
Shouto felt stung and suddenly jarred awake. He was still very turned on, but also alert and worried. What am I doing? He turned and watched Izuku pull his jeans down along with his briefs, letting loose a hard dick that was as long and thick as any Shouto had ever been fucked with. Izuku's body was incredibly muscular, but even against the bulging muscles, his dick seemed oversized, with large round balls below it.
Shouto thought, Is this really happening? Am I really going to let this happen? Frozen in indecision, he watched Izuku pull a bottle of lube and a condom from a shelf. Then the older man noticed Shouto staring at him. Grinning, he slapped Shouto's ass again.
Shouto jumped, irritated but also incredibly turned on. His ass felt bare and cold in the backless briefs, and he realized he needed to put a stop to this.
While Shouto tried to figure out what to say, Izuku popped open the lube bottle, poured some over his fingers, then reached out and slid them right into Shouto's crack. They immediately felt so, so good. Surprising himself, Shouto turned back to the wall and pushed his ass back against Izuku's hand, helpless with his need for more. I'm like an animal, with no control, he thought as Izuku's finger zeroed right in on his hole and began pushing inside. Shouto opened his mouth to say, "Stop," but then Izuku's finger was in him, and quickly pushing deeper.
Shouto gasped and Izuku paused, but only for a moment, his finger slowly rotating, steadily building up the pressure. Shouto felt like he had to tell Izuku to stop, but he didn't want it to stop, and then Izuku's finger slipped fully inside him and it was like it belonged there. Shouto bent over and felt himself open up to Izuku, as the muscular man's finger curled down and found Shouto's prostate, creating an incredible pressure that totally took over Shouto's body. Involuntarily, he grinded back against Izuku's hand, opening his ass to the older man, and he could feel his precum dampening the pouch of his backless underwear, which was holding tight on his hard and painfully curving cock.
Izuku grabbed Shouto's body with his free hand and felt him up, while pressing his rock-hard cock up and over Shouto's quivering ass.
"You're so tight," Izuku said. "You sure you want me in there?"
Shouto wanted to say no, but he felt like the finger in his ass was pushing a button that forced him to say something else. "Y-yes," Shouto gasped.
"You want it?" Izuku asked.
"Yes," Shouto said, ashamed, whispering, hoping that Izuku would just do it.
"Show me," Izuku said.
Shouto sighed, frustrated, but then his body moved as if on its own. He bucked his hips back, rotating them around Izuku's finger deep in him, and then suddenly Izuku slipped another finger in, making Shouto gasp.
"Good," Izuku said, grabbing Shouto's upper back and pushing him down, so that his ass was pressed even more fully onto Izuku's fingers. He started twisting them around each other as he pushed deeper into Shouto, who shuddered from the sensation.
And then Izuku slowly pulled his fingers out and Shouto opened his eyes, seeing the wall of the storeroom in front of his face, and again he felt unsure. The heavy weight of Izuku's dick slid across his butt cheek and then off of him as the older man stepped back, and Shouto suddenly felt a little afraid of Izuku and his size. What would even happen if I tried to say no?
Shouto straightened and looked back to see Izuku expertly ripping the condom out of its wrapper and sliding it over his large, rock-hard cock. He rubbed lube on it, and then fully turned towards Shouto, grinning. "Time to fill you all the way up," he said.
Shouto tried to clear his head, to come up with a plan to end this before it went further, but then Izuku grabbed Shouto's ass, slipping both hands under the backless briefs, down the side of Shouto's cheeks, and using his thumbs to spread Shouto wide as his dick slid toward the younger man's hole. Shouto gasped from the sensation, suddenly needing Izuku's cock to hit its destination. Almost hypnotized, he turned back to the wall, bracing himself with his hands, knowing there was nothing he could do now but wait for Izuku to enter him. The lube on the older man's dick was wet and a little cool on the skin between Shouto's ass-cheeks, and then he felt the large, round head of Izuku's cock pressing against his hole, steadily harder, until it was pushing into him.
Izuku slid his hands over Shouto's ass, using his thumbs to point his dick down and into Shouto. Shouto arched his back as the incredibly large dickhead pushed, and pushed hard, and then popped into him. Shouto moaned.
Izuku stopped and held his cockhead just inside while the younger man shivered around it. Izuku lifted one hand up to Shouto's neck and tightened the other on Shouto's waist, so that he could hold Shouto straight as he slowly began sliding the rest of his shaft inside the boy.
Shouto felt like he couldn't possibly hold it all as the dick pressed up against the sides of his hole, filling him with warmth and throbbing hardness. Izuku's thick, muscular legs brush up against Shouto's, and Izuku's dick just kept pushing deeper, deeper into Shouto, so that he felt he had to cry out in protest, but he didn't. Instead Shouto kept breathing and holding it in, until Izuku was so deep in him that he was sure no man had ever been so far inside.
"Oh, yes," Izuku said, in control but with a heavy voice. "You really needed this. And it feels so good and tight."
Izuku was slow at first, sliding in and out, getting Shouto used to the sensation. He pulled Shouto back by the shoulders, so that his back arched to make his ass perfectly positioned for Izuku's driving cock. Then the older, muscular man put both of his large hands on Shouto's hips, sliding them under the band of his briefs.
The sensation of his warm, tight grip there, and his heavy body pressing against Shouto's butt cheeks as Izuku's massive dick piled into the boy, was almost too much. Shouto opened his eyes, trying to find something to focus on, to anchor his churning mind and body, but all he saw was his hands against the wall of the storeroom, beginning to slip as Izuku's fucking grew faster and harder.
With a feeling of unreality, Shouto thought, This is really happening.
"You're so fucking tight," Izuku said huskily, over the slapping of his hips against Shouto's ass-cheeks. "It's making me so hard."
Shouto, his insides starting to feel pummeled, slid down the wall, bracing himself on an elbow so he could reach down to clumsily adjust his hard-on in the tight briefs his cock was painfully straining against. He was getting shaken back and forth by Izuku's rough pounding, but he finally managed to slip his dickhead out of his briefs' pouch and to the side. He moaned at the release of pressure, but then the tip of his cock started brushing up against Izuku's hand on Shouto's hip.
Each time Izuku slammed his rock-hard dick deep into Shouto, it was followed by the warmth of the man's hand brushing against Shouto's cockhead, and Shouto gasped out, "Wait, wait, I'm going to come!"
Izuku kept driving deep into Shouto as pressure, like a volcano, built along Shouto's shaft, and he could feel the tip of his dick slipping in its precum along Izuku's hand as it thrust, thrust, thrust forward with each pounding from the muscular, older man.
"You told me I wouldn't come," Shouto whimpered, thinking, But I want to so badly.
He gasped as Izuku suddenly pulled out of him. It was shocking and uncomfortable to have that giant dick yanked away.
"You're right, I'm sorry," Izuku said as he stepped back. "I forgot this is just a warm-up."
Recovering his breath, Shouto turned and was awed by how incredible Izuku's body looked, shadows falling across slabs of muscle, all angled in tight lines down to a pulsing, massive cock pointing out like a missile.
Izuku roughly grabbed Shouto's crotch, and Shouto could feel how wet with precum the underwear was. The older man grinned. "I'll have to give these to you as a free pair." Then he looked Shouto up and down leeringly, his expression drunk with lust.
He grabbed the briefs with both hands and yanked them down. Shouto thought, You told me you'd leave them on, but instead of protesting he stepped out of them. Izuku pulled a stool from the wall and placed it in the center of the storeroom, and then he draped the wet underwear over it. Then he grabbed Shouto by the waist, effortlessly picking him up and sitting him on the stool. Before Shouto knew what was happening, Izuku had grabbed Shouto's thighs and was pushing his cock back between Shouto's ass cheeks.
Shouto rocked back on the stool and arched his ass up to meet Izuku's searching cock. Hard and insistent, it found the younger man's hole and pushed inside.
Shouto felt shocked all over again at Izuku's giant size, sliding in and hitting him in places no man had ever reached. He wrapped his legs around Izuku, pulling him farther in.
Izuku was faster now, getting quickly up to speed at pounding into Shouto, while his muscular body surrounded the boy, large slabs of muscle hanging over Shouto, Izuku's bulging arms holding him in place as Izuku's fucking shook his insides in a way that felt increasingly right, increasingly overwhelming.
Soon all Shouto could see and feel and think about was Izuku's massive body piling into him, and how his own body opened to meet the man's every thrust in the deepest, best fuck of Shouto's life.
Izuku grunted, beyond words, and his tight, sweaty abs rubbed across Shouto's hard, leaking cock. I'm going to come, Shouto wanted to say as the pressure built up, but he couldn't speak; he was too overwhelmed by the weight of Izuku's heavy body pressing down against him.
Izuku began to grunt with each thrust, sweating harder as he sped up his pace. He's going to come in me, Shouto thought, and that put him close, too close. He cried out as the pressure in his cock grew and grew, pushed forward by the pile-driving from Izuku's dick, so hard against and through his ass, and then pure, hot joy filled Shouto's lower body and cum exploded out of him, bathing both men's stomachs and chests.
Izuku straightened up and grinned down at Shouto, slowing his thrusting. Shouto luxuriated in the lengthening of his orgasm, moaning rhythmically as his cock jerked and more come spurted out, and each time he thought it was over he looked up at Izuku's glistening, massive body, still pushing back and forth into him, and another wave of orgasm shot through him and out of his twitching cock.
Izuku's eyes narrowed at the sight, and then he gripped Shouto's hips tighter and sped up again, pushing Shouto's ass hard onto his cock, going as deep as he'd gone yet, so hard it almost hurt. "So. Fucking. Tight," he gasped, and then he let out a low shout and arched his back, and Shouto was shocked by how hard and thick the muscular, older man's dick felt inside of him. One last spurt of come slipped out of Shouto's cock as Izuku's shuddering body unloaded into Shouto's ass.
Finally, Izuku collapsed over Shouto. "I fucking love it," he whispered, and then he began to kiss Shouto's face. After a long moment of that, he slowly eased away.
After pulling out, he stripped off his condom and held it up, displaying the big pile of cum inside its tip. He grinned down at Shouto. "That was... awesome."
Shouto, who felt like he was slowly coming down from a religious experience, said without meaning to, "You're the best top who's ever fucked me."
Izuku slapped Shouto's ass. "Then go pick out some new pairs of underwear for me to fuck you in, and let's make a night of it. I live right around the corner."
Shouto thought, Will Katsuki even notice or care? And then he realized that the only thing he cared about was getting Izuku back inside him.
Late, late that night in Izuku's bed, after Shouto had tried on everything from too-small briefs that didn't fully cover his crack to a tight pink jock strap with "slutty bottom" written on the waistband, the muscular, older man was sliding his massive dick deep into Shouto for the fourth fuck, and Shouto was so glad he'd given in, again and again and again.
