Big Boy Undies: Brother-Fuckers Collection

 

 

 “Dustin what the fuck!” I shouted walking into my room, seeing my younger brother on my bed in my boxer briefs.
 
“Oh, hey bro,” He sat up slightly after having enjoyed a nap in my space completely unbothered. There was something in his cadence that annoyed me, the fact it was my cadence. My attitude, my brain, He even looked as old as me. His body had co-opted all my hard work and given him the muscles and height it took years to achieve, all because he put on my underwear.
 
The worst thing about it? It was hard to stay angry seeing the fat ass I had given him. And fuck if his balls didn’t look as full as mine laying there, legs spread open.
 
“Don’t ‘hey bro’ me,” I replied. He even had on my dress socks. He knew I only had one pair of those for job interviews. “I knew you took my underwear this morning! I had my whole outfit planned out.”
 
“I assume that means you didn’t get the job.” he stated
 
Rolling my eyes, I did air quotes “Oh ‘assume’, look at you using big words from me.”
 
“Look bro, regardless of what you were wearing or not. If they didn't give you the job it wasn't meant to be.”
 
He was using my own reasoning against me. How many times had I said that to friends to calm them down? Well guess what, my words weren’t working on me. “So what, I sweat out my interview while you’re living large. Mom and dad thinking I’m just sleeping away in here.”
 
“It was a nice nap.” he laughed my laugh, but in his new deeper voice, which by the grace of the universe wasn’t a copy of mine. Small victories.
 
“I bet.” I spat, putting my bag on the floor.
 
“Look instead of being mad, let me make it up to you.” he stated.
 
“How do you plan to do that; you steal a job opportunity from me too?” I started pulling off my suit.
 
“No,” he chuckled. “Come fuck my ass, take a load off, dump a load.” He spread his legs wider, that perfect rump on display. Offering my ass and cock was a specialty of mine, never something I thought my brother would pick up from me. But honestly after the shit day I had I needed it. Pulling off my tie I climbed into the bed behind him. After stealing my shit, he was going to be taking more than a load.
 
—

 

Eric Chang had no idea putting on his brother's jockstrap would feel so good. The undergarment had been strangely abandoned in the center of his room. His older brother, Quay, had once been a studious academic under his parents roof, but 4 years at college had turned him into a complete musclehead. Sometimes Eric would almost forget they used to share a room, bunk beds. Until their parents demoted Quay to the guest room thinking he’d be a bad influence on Eric. Quay’s bed was out and a new desk for studying was in.
 
There were times Eric wanted to scream into his pillow. He had been a good student, but he was never a great student like his brother. His parents never really cared about his performance until Quay grades plummeted. Even when Quay was home, his parents couldn’t get him to care. Eric even tried to talk to him once.
 
“Little bro,” Quay would say with that kind smile, “You got to let Mom and Dad’s expectations go. That’s what I did, and it freed me.” His voice would say calmly as if he were a guru. 
 
Easy for Quay to say, he was away at college. He didn’t have mom and dad watching him like a hawk. So how did that lead to Quay just dropping trou, stepping out of his jockstrap and walking out the room bare ass naked? But Eric wasn’t focused on him, only the garments he had slipped out of. He couldn’t look away. He wanted to put them on. HAD to put them on. Walking over in a trance-like state, he disrobed and got his brother’s jockstrap.
 
The moment it was on, his body was completely different. The height came first as his body bulked with muscle. His pecs pressed out with a clear division between them. He never put his older brother’s clothes on; they simply appeared on his body. Eric went from student to pure jock in record time. Chewing on Quay’s tank, he tasted his older brother’s sweat, as his ass stretched the jock strap. Veins ran across feeding his muscle into an even more disciplined version than his brother.
 
Quay knocked back on the door, walking in when he heard the moaning. Their lips were soon on each other. The Changs would be disappointed to learn their dreams for another son were once again dashed to chase balls, in various forms.
 
—
  

“Hahaha, won’t go down, will it?” Lenny laughed. The bet was simple, have Blake wear his underwear, after complaining about Lenny’s constant boners. Lenny was too used to college life and just constantly rocking them out in the open. His little brother wasn’t having it though. He didn’t believe Lenny’s “It just happens” excuse.  Blake was so smug, in the way most younger brothers were. He wasn't prepared for the rush of Lenny’s hormones into his system, when he got those American Eagle’s on.
 
Blake got hotter, taller, but he also got hornier, pitching a tent every which way he turned. 
 
“That’s what having a real dong is like bro, you get lost in it.”
 
“But it’s just there, and so needy. I NEED TO FUCK SOMETHING, bro!” Blake’s cock throbbed with each word. “How do you do anything with this in between your legs?”
 
“Ehh, sports help. You can thank me for the body later—mass looks good on you—it’ll be great when you start signing up with me at my university." Lenny lay comfortably on his bed, watching as Blake stared down at his new boner. The older brother had to stifle a laugh, not mocking him, but it was kind of adorable how lost Blake looked in Lenny’s underwear. “And when you’re not practicing, a lot of the guys will be willing to help you clear your head, if you catch my drift.”
 
“Okay, but what do I do with it NOW!” Blake asked, “I’m not even going to be able to go to class without thinking about slipping it into someone.”
 
“Stop being dramatic, dude.” Lenny sat up, fully facing his brother. He pointed to Blake’s dick, “That’s your new North star, courtesy of me. And if it’s giving too much trouble, you should let it lead the way.” Blake looked down at his boner, then followed to where it pointed to Lenny on the bed. A knowing smile, Lenny beckoned his brother closer with a finger. Blake slowly walked until he stood over Lenny’s lap. Yanking the boxer’s down, Lenny let Blake’s cock spring out, then grabbed at his younger brother’s ass. A powerful shove from behind, Blake’s cock disappeared into Lenny’s throat. 
 
Blake writhed and drooled over the foreign sensation. Following his big brother’s embedded instincts, Blake placed his hands on the back of Lenny’s head. The two found a pace with Lenny setting the lead, until he wasn’t. A switch went off in Blake and his body took over, shoving Lenny down on his cock, skull fucking his big bro, until his cock christened Lenny’s throat with heavy cream all gulped down. Blake’s cock fell out of Lenny’s mouth, defeated and coated in saliva. Finally, he could think again. All horny thoughts catapulted down into his brother’s stomach, for now.
 
Then Lenny wrapped his hand around his brother’s waist and pulled them both back into the bed, then flipped on top of him. “Now, it’s time I follow my north star.” Lenny smirked with the heat of his dick stuck between their two bodies and only growing warmer.
 
—

 

Okay, Tyler don’t freak out. Sure, you took your big brother's underwear. He’s a marathon biker and was out at the time. BUT how would you know that it’d make you grow? It was hard peddling down the street as your small body began to press against your clothes. Was it your shirt or shorts that vanished first? You can’t remember. What was easy to remember was your longer legs, jumbling up the vehicle making it hard to maneuver. Adjusting your posture, to keep momentum and not crash, your spine snapped straighter. Poor Tyler, you didn’t even know your butt was blowing up, swallowing up the seat.
 
When the bike changed, that was more concerning. The entire design lost its electric blue for a slate-gray, as the front pulled forward. The wheels got thinner as their radius expanded. That’s when your shirt popped off as your chest came into fruition. Oh, you could barely see over those tits as you went on. Why couldn’t you stop? Maybe it was your ass thrusting you higher in the air, generating more power, pushing your journey further.
 
Come on Tyler, your short’s split and your brother’s underwear was out. Your secret was exposed, no one was looking, but the whole world could see if they wanted to. That’s when your face changed, jaw sharpening as your throat reformed to hit a new register. Then came the bulge, your cock had never protruded in that way before, but your brother’s did. The tattoo on your legs, the chain around your neck, your hat turned backwards on your head, All your brother’s style.
 
You finally came to a complete stop, able to get your body under control. Sitting off the dusty road’s edge was your brother looking smug, knowing what you’d done. Realization hit hard. From the moment you picked up his underwear, your inner monologue was his voice. MY VOICE. 
 
Heh, didn’t think you had it in you little bro: To steal my shit. Did you enjoy having me in your head? That bulge in my underwear sure looks like you did. Now get over here so I can get a closer look. 

—

 “Let’s get this clear Ty, I didn’t tell you to do shit,” Jeremiah stated. Two black men were currently in Jeremiah’s room where only one had existed second’s prior. Jeremiah was standing up looking over to what should have been his younger brother in the gaming chair.
 
“I know,” Ty rubbed the back of his head,” But all the cool stuff is in your room.” He spoke with a voice far deeper than he had ever possessed. His body was immaculate plucked from Jeremiah’s wettest dream.  Never in his life would he ever think he’d have such an effect on his younger brother. The boy had been turned into a man in every aspect, the facial hair, the pecs, eight abs. More importantly Jeremiah’s compression shorts that Ty was wearing were the real star. Thick, skull crushing thighs and a fat ass being sat upon, appetizers too the long cock very visible.
.
Jeremiah looked good in his compression shorts, but Ty had made the damn things his bitch. It was surprising the thin material hadn’t given up like the rest of Ty’s clothes. Ty knew better than to sneak into his brother’s room. Surprisingly, it wasn’t Jeremiah who had banned Ty from his room rather than their dad. 

His words being to them both, “Look Jeremiah’s like me. He’s a whole lotta man, it’s hard not to be influenced by him. He needs his own space.” At the time Jeremiah just thought that was his dad’s way of saying he was going through puberty. But now it seemed his dad actually had a point in keeping Ty out. It was like Jeremiah’s Compression shorts channeled his testosterone directly into his brother. And holy fuck did his brother look more potent than him. 
 
“Ugh, Dad’s gonna kill me,” Jeremiah dragged his hands down his face. 
 
“Yeah maybe.” Ty responded in Jeremiah’s laid-back type-tone, no care whatsoever.
 
“He’s probably going to kill you too.” the words were said to get a specific reaction out of his brother that never came. 
 
“Well then, he’ll kill us when he gets us. But no use in just wasting time. I gotta drain my balls and I bet you do too. Might as well stroke it out.”
 
Jeremiah shook his head, Ty got his horniness too, but if they were in trouble any way…draining his balls now with a stud was as good of a time as any.
 
—

Jordan stole Randall’s boxers out of the washing machine. It was early morning and no one else was going to know. Randall, his older brother, had moved back in with the family after college, and Jordan often caught a glimpse of the boxers. Mysterious things. And now here he was, having slipped them on looser and freer than the boy briefs, their mom condemned Jordan too. The novelty only lasted a moment as a surge erupted inside of Jordan. His young body shook and the house shook with him. Jordan couldn’t utter a single word as his body snapped and popped. His height was soaring, body changing.
 
No one came rushing downstairs, despite all the commotion. Only Jordan saw his action figures, scattered across the living room, get shaken out of existence, fading into nothing as various dumbbells replaced them. His shoes by the door stretched mouths widening as Jordan’s soles expanded. The plain design was overwritten by an athletic one. They didn’t stop until they were almost indistinguishable from Randall’s in size. In the end, two sets of tennis sat next to each other. On the coat rack, Jordan’s coat morphed as the heat in his chest encouraged it to. His traps shoved his shoulders aside so that his chest could pump up. As pecs rose to prominence, abs formed following their example. A healthy dose of muscle mass was forced into his arms and legs, earning him jock proportions. His new coat hung, slim, stylish, and large.
 
A change erupted across every family picture as the still images of Jordan went through the same transformation. The integrity of Jordan' s face gave way as his bone structure removed all fat, accentuating its own features for an older look. His mop of curly hair whipped up and reformed itself into a trendier look, trimmed on the sides, curls kept at the top and front. A cut reminiscent of Randall’s sensibilities. Meanwhile, the photos stamped Jordan’s new face into their ink, solidifying it in reality. Jordan stumbled back, body hitting the counter with force. The house’s shaking finally stopped.
 
As Jordan looked down at himself, he saw not only his brother’s boxers, but Randall’s chain and socks as well. Well, they were brothers. Twins even. It wasn't odd for them to borrow each other’s stuff. He had snuck down here to have something to wear. Right? Maybe more curious was the boner Jordan was getting. Pitching a tent in his big bro’s underwear?  He didn’t usually go around popping boners. Actually, he couldn’t even recall the last time he did. Oddly it felt like his first. Oh well, maybe his brother would have some answers, once Jordan woke him up. Randall had always loved Jordan’s cock up his ass for a morning rise.

—

 

 

Wesley was shocked when he stepped into his bathroom, and found his little brother, Milton, wearing his socks and red Hanes boxers. It was supposed to be Wesley’s private area hence the half-naked man on the wall by the toilet. He finally had his own place, and a private bathroom even his parents couldn’t see. Why did he allow his brother to come visit him?
 
“Personal space much?” Wesley stated, trying to downplay it. He scratched his head; there was something off about Milton. Not the stance: One leg bent up on the tub, the other still on the floor, arms crossed. Milton was always trying to show off. A good pose considering all the muscle he was packing. His biceps looked extra nice.  Maybe that was it, had he filled out, bulked more…nah Milton had always been big. Then again, had he? Wasn’t he visiting during semester break—
 
“What’s this about?” Milton nodded his head back to the photo.  
 
“It’s a guy.” Wesley shrugged, not dealing with this.
 
“Yeah, no shit it’s a guy. Why’s it in your bathroom?” Milton asked.
 
“Why do you think?” Wesley shot back. “Here’s a better question, why are you? And why are you wearing my clothes?”
 
Milton looked down at himself, confused. “I am?” he looked around, “Did your bathroom get smaller?” 
 
“No.” Wesley sighed, “Must have been all the weed you’ve been smoking on tour. “I see you got another tat,” He pointed to Milton’s arms covered in a respectable smattering of tattoos.
 
“Hey, first of all, it’s hard being a rockstar. Secondly, I haven’t smoked since the last time I was here. Thirdly, tatts look cool.”
 
“You haven’t, why not?”
 
“Don’t know, I think my big brother said something about liking my natural smell last time? So, when the band came into town I figured I’d use my spare key to sneak in. Thought it’d be nice to put something of yours on.”
 
“And?”
 
“And I was right; your shit is comfortable as hell.” He leaned forward on his bent leg.
 
Wesley smirked, strolling into his bathroom and kissing Milton, until his younger brother’s cock begged to be freed. Reaching into the waistband, Wesley stroked it. How long had the two been seeing each other like this? Had to be years at this point. Honestly, Wesley couldn't quite remember how it started, perhaps catching his brother in his underwear even back then. Milton looked up to the then-punk teen so maybe it was fate, Milton would start working out and form a rock band. Now, he toured all over the country but always made stops at his brother’s city.
 
“I want that guy gone.” Milton said between kisses, “Then I’ll fuck you.”
 
“Fine.” Wesley relented, “But I will be putting a picture of you up there.”
 
“Good. Should have done that in the first place.” Milton growled with pleasure as his brother continued jerking him off.
 
—

Santiago, are you happy now?
 
Why did you take the underwear? Was it just because it had Batman on it? Who are you kidding, of course that’s the reason. They weren’t boxers or even boxer-briefs. They were FULL ON BRIEFS. What was your older brother doing rocking briefs? When did he wear them? Why did he wear them?
 
If anyone in the house deserved to wear briefs, it was you! So, snatching them up wasn’t stealing, it was justice. You slipped them on in the living room. The warmth was unbearable and it started all at your crotch. It bulged like a lump, right over Batman’s body as your glutes swelled in the back. Next it was your legs, sending you higher in the air as hair began to poke over them. Thighs expanding, calves bulking, feet extending. It looked like your brother’s legs were attached to you. Pecs rushed out of your chest, spilling into the air with dark nipples.  Your shoulders were titanic, compared to before and spread wide. Arms that looked more appropriate on a warrior found themselves attached to you, biceps and forearms ready. Your face was the last to go, stubble rising over your lower jaw, eyebrows growing bushier. When your head elongated as your jaw lengthened. Did it feel good? How about when your hair reshaped into your brother’s proper style, dark strands brushed down perfectly.
 
Then it was done. Was wearing your brother's briefs everything you hoped it would be? You were as old as him, standing in his underwear. Felt awesome to stroke your cock as memories rushed into your head, matching you to your body. Of course, your legs shook when you came, as your new balls shot (their first load into your brother’s undies.) Thank God the windows were close or the whole neighborhood would have heard you. (Was your first orgasm everything you dreamed it would be?)
 
Your brother found you. ‘Found’ wasn't the right word. He was the only one home to hear the moan you let out. A moan that sounded eerily similar to his yet had not left his mouth. He came downstairs to find you Santiago, still spewing ropes into his underwear. 
 
That led to this interrogation: you hiked up on a chair, defiant with all of your older brother’s confidence. No conscious awareness of what you were putting on display for him. Was it the third or fourth time his eyes homed in on your package, that little Santiago started responding to the attention. Now Santiago, you knew exactly what you were doing when you thrusted your hips forward. Your package jiggled and more of your ass was on display. Whatever speech your brother had been giving you, stopped completely. He knew what you were offering for him to shut the fuck up. And he was going to take it.
 
Oh Santiago, you’re very happy now, aren’t you?
 
—

Hayden snapped the photo for proof, texting it directly to his friend. “Dude, I’m fucking telling you this is Bennett. My lil bro put on my underwear, I think our dad mixed them up? and turned into a fucking Adonis in his own right.”
 
Smith’s reply was quick, “Wait, so you still wear tighty-whities no wonder your dad mixed them up 😛.”
 
“Be so fucking for real right now bro, briefs give me the best support. Not that I’d expect you to understand needing that.” Hayden typed back, moaning.
 
“Ouch, you've wounded me 😂. But come on, I can tell that’s you. Like you even forgot to take your socks off. And as if I wouldn’t know that ass and bulge outside of the locker room. Don’t know why you’d AI an older version of Bennett’s face on it though? Your face is (mostly) hot enough.” Smith’s joking voice was radiating through the electronic message.
 
Hayden sighed, fingers working, as he adjusted his seating. “Look, I get that he kinda resembles me. Like those are my pecs and abs sitting on his body, my height that he’s strolling around the house in. But underneath that, it’s still him. He put my socks on because he likes them.  He even got his morning OJ. When’s the last time you’ve seen me drink OJ? Never!”
 
“Are you bragging about being vitamin C deficient? 💀 Weird flex, but okay.” Smith’s phone was still typing then sent, “So your briefs made your brother older? Okay I’ll bite, how’s he adjusting?”
 
Thrusting his hips excitedly, Hayden responded. Finally, he could talk about the weirdness of that morning with someone. “That’s the thing, Bennett’s fine. He wants to be called Ben now. He’s even listed on our university’s swimming team. Right between men and you, but like no one remembers him.”
 
“Holy shit so your underwear recruited your little bro, That’s kind of awesome! What are you going to do now?”
 
“Don’t know. Maybe I can start selling my underwear on eBay or something? People might pay good money to have their kids turn into swimmers.”  Hayden took a hand off the phone, running it through hair.
 
“Idiot, I’m talking about your bro, not your wallet. I mean even if the coach accepts him on the team, he has to do initiation. The team isn’t going to go easy on him, especially looking like that.”
 
“What do you think I’m doing, dumbass.” Hayden smugly replied.
 
“You fucker.”

Hayden leaned over to toss his phone on the dining room table. He was seated far from its edge and in between the gap of his chair and the table was Ben on all fours sucking his cock. After downing his orange juice, Ben immediately began to service Hayden. A common practice of the swim team at his college. Their team building ritual where a senior like Hayden expected underclassmen to clamor for his cock. Have your teammates’ kids swimming inside you, while you cut through the water. He never thought his younger brother would be the one doing it. Or that Ben would know exactly what made Hayden’s cock hard. Ben gargled Hayden’s balls, huffed his blond pubes, then would just swallow his dick in one motion. He had acquired Hayden’s deep throating skills. 
 
It was so damn good, it felt like an edge session. Hayden wanted it to last and also wanted to blow. A master in his own right, Ben won his older brother’s cum. Hayden’s cock spewed endlessly as he reached his crescendo. Creamy brotherly ropes shot across Ben’s tongue and down his throat.  Ben sucked slower, coaxing more of his nephews out of his brother's cock. When the dick was dead, fat as fuck but limp, Ben let it drop out of his mouth and slap against Hayden’s thigh.
 
“Looks like you saw heaven bro,” Ben laughed down on the ground, looking up at Hayden wrecked.
 
“I didn’t…know you kept… heaven in your mouth.” Hayden said, catching his breath between words.
 
“Heh, maybe I have what it takes after all.” Ben flipped his hair out of his eyes.
 
Hayden’s eyes narrowed playfully, “Don’t get cocky,” He picked his brother up off the floor and sat him on the table. Leaning forward, arms locking Ben in protectively on each side, Hayden kissed his younger brother’s chest, then his neck, until their lips found each other. The taste of his jizz wasn't so bad on Bennett's lips. “That was only phase one. The guys on the team like to test personal stamina too.” Hayden gripped at his underwear on Ben and began to pull down. A cock as beautiful and long as Hayden’s slapped Ben’s abs.  Hayden was going to enjoy milking this one.