Mark was your average high school senior. At 18 years old, he still wasn’t much to look at, and wasn’t super popular either. It’s not like he was a bad looking guy, just stick thin, unhairy, and short. He had black hair, and brown eyes, stood 5’0” and weighed 110 pounds. His facial hair hardly grew in so he shaved his face clean every morning. He had a handsome face, with a medium nose and cheerful eyes and smile, he just usually went unnoticed by his classmates because he was so small. The growth spurt he’d waited on never came and he was done growing now.
Mark’s uncle Julian was staying with him and his parents. He’d had some big fight with a girlfriend and had to move out. Julian was 30 and from what Mark could tell had a really great muscly body. He had short spiked black hair and a neatly trimmed black beard and mustache. He weighed 215 pounds and had more muscle than fat, but he didn’t have one of those freakishly low fat percentage bodies. He was 5’9”, not the tallest man, but taller than Mark would ever be. Julian was currently sleeping on the couch with his head detached. He claimed that it helped prevent neck soreness.
Mark had to go to school today and worse, he had to do the swimming unit in gym class. That meant stripping down to nothing in front of the other guys and putting his scrawny body to the test in the pool. His build wasn’t really the most embarrassing part of that, it was his penis. His balls were a good size with a good hang, and his penis was a good length, but he had a little less girth than average. When erect, Mark’s penis was seven inches long but with only about the thickness of a couple fingers pressed together. It wouldn’t have much penetrating force to go inside anybody who wasn’t already loose.
Mark thought about the humiliation awaiting him at school, in first period no less. His mind flashed to his uncle sleeping on the couch. He couldn’t...could he? Mark had never head swapped before. His parents were mostly against it. They had done it a couple times with each other but had forbidden Mark to experiment.
Mark decided that it was easier to ask for forgiveness than permission. He propped Julian’s body up on the couch, popped his head off painlessly, and placed it onto his uncle’s hunky form. As soon as he was in control of Julian’s body, his former body fell against him. His former body was a welcome weight on his new lap. It started to make Mark’s new penis hard, but he didn’t have time to explore all of that. Mark got up and placed his original body on the couch, lined up with Julian’s head. He carefully connected his uncle’s head to the 18 year old body so as not to wake him.
Mark wrote a small apology note and left it on his uncle. It read,
“Sorry for borrowing your body. It’s just for the day, I promise,
Mark”
Mark headed out to catch the school bus. He forwent a coat, thinking his uncle Julian’s muscles would keep him warm on the cool 50 degree morning. As he waited for the bus, the somewhat chilly morning breezes kept hitting him. It was making his new nipples on his large pecs grow hard. Out of curiosity, and after making sure nobody was looking, Mark fondled his new tits. They were so hard and sensitive. His former nipples were so flat compared to these, even when those ones did get hard they were more like mosquito bites instead of the tic tacs he was currently stowing in his black t-shirt. He smiled in amusement as he kept playing with his uncle’s tits. It was making his new dick really hard in his jeans. For a moment he wondered what kind of underwear Julian was wearing before their swap and what his dick looked like, but then the bus turned the corner interrupting his incestuous gay thoughts. He stopped playing with his chest before anyone saw and luckily his boner was going straight down in his jeans invisibly as he loaded himself onto the bus.
Mark was getting looks left and right on top of his uncle’s body. Even the bus driver looked longingly at the boy as he got off of the bus. He strut his stuff, or rather Julian’s stuff all the way to the boys locker room. He couldn’t wait to see what he was working with under these clothes. He walked into the locker room with all of the other 18 year old senior boys he had gym with.
“Dude, your parents let you do a headswap?!” Asked Jason, Mark’s best friend. Jason’s parents hadn’t forbidden him from headswapping, but people weren’t exactly lining up to give a teenage boy their body.
“Not exactly, I—“ but Mark was interrupted by coach Stevenson.
“Mark! You know I don’t allow headswaps for the swim unit. I’m gonna have to confiscate that,” said Mr. Stevenson.
Confiscate what? His uncle’s body?! Mark could only wonder as he followed the middle aged coach to his office.
“Go on, pop your head off, what are you waiting for?” Asked Stevenson.
“But I just got this body!” Said Mark in protest.
“I’m not asking. You’re gonna spent the period in here in my body as punishment for trying to break my rules,” said the coach.
Rather than argue with him, Mark accepted his punishment. At least it would just be an hour spent in the coach’s body before getting Julian’s body back. He popped off his head for the second time today and set it on the desk. The coach took Julian’s body over and checked himself out, squeezing his biceps and powerful thighs. Mark wanted to do the same but thought better of potentially angering the coach.
“Alrighty, have fun in my office. You’ll still get credit for the day, but only because this body you gave me is killer,” said Mr. Stevenson with a wink and a smirk. He stripped down to uncle Julian’s tighty whities. So that’s what Julian was wearing when Mark swapped with him this morning. He had only a few seconds to see Julian’s junk in the tighty whities before Mr. Stevenson headed out to start teaching the swim unit. Hate to see you go but love to watch you leave, thought Mark as the coach’s new muscly bubble butt jiggled perkily with his gait.
Mark ran to the mirror in the office. What sort of phys ed office had a full length mirror anyway? Greeting him was his same handsome face he’d always known atop a six foot tall body with a surplus of fat. Don’t get it twisted, Mr. Stevenson’s body did have a good amount of muscle, but he definitely had a beer belly and man boobs too. Mark stripped his shirt off of his middle aged body.
“Oh mann,” complained Mark, “This body is so fat. Though it is still a man’s body... Maybe this could be an enjoyable masturbation experience.”
Looking at himself in the mirror Mark started to rub his nipples like he did in Julian’s body whilst waiting for the bus. This chest, unlike Julian’s, was covered in hair and a good layer of body fat on top of the muscle. These nipples were so responsive, they hardened with no chill in the air and sent waves of pleasure through his body, resonating in his prostate.
Mark found himself grabbing his new pecs like the boobs they were. He fantasized for a minute about letting his straight friend Jason fuck his new hairy man cleavage. He couldn’t believe he thought this body was a punishment five minutes ago.
Something demanded Mark’s attention in the front of his khakis. His boner felt large and was aching to cum. Mark undid his belt and dropped his pants to the floor and kicked them and his shoes away. Now all his eighteen year old head and fifty year old body had on was Mr. Stevenson’s choice of underwear. It was a cheetah print pair of mens bikini briefs. Mark had to admit that these accentuated the highlights of coach’s body. His backside was enormous, but strong and shapely. The fabric clung tantalizingly to this daddy ass, making it look even more appetizing and fuckalicious.
The front side of the bikini briefs was perhaps equally arousing. Underneath his hairy beer belly was a front bulge which indicated a relatively short, fat dick, and a good large set of balls, which were twitching with semen production. He pulled down the front to examine his new dick. It was a five inch erection with impressive girth. This cock was not only twice Mark’s original thickness, it was also as hard as a rock. He’d have traded two inches of length for this much girth any day.
Mark pulled the cheetah briefs back up over his thick cock and big balls. He wasn’t ready to shed the underwear just yet. Instead he turned to the side so that he could see his ass and his new junk in the mirror at the same time. He then jumped up and down, watching his ass, crotch bulge, beer belly, and man boobs jiggle gloriously. He kept on like that for a while, practically hypnotizing himself. It was so erotic watching this manly body bounce around. Mark would never see coach Stevenson the same after this. His cock started leaking just from enjoying the show.
“This perverted ass teacher has got to have some lube or something in here,” said Mark as he began rummaging through the office.
What Mark found in one large desk drawer was so much more than just lube. In it was a dildo, handcuffs and key, a bottle of lube and about a million pairs of underwear. The weird thing about the underwear was that many were different sizes and vastly different styles. Were these all trophies or something?
Mark grabbed an xl pair of boxers from the drawer to use as a cum rag, along with the dildo and lube. The dildo looked really familiar. Mark pulled his bikini briefs all the way down and discarded them. He held the dildo up to his new penis. It was a perfect match for his new cock, down to the vein that protrudes on the left side. It must’ve been a custom dildo made in the perfect likeness of Mr. Stevenson’s dick. The thought of feeling a copy of his dick fuck him made his fat sausage member start leaking more pre cum.
It was time for Mark to lube up for the big battle with the thick dildo. Since Mark lived in the boondocks, he hadn’t been able to get his first job yet and therefore he hadn’t bought himself any of the sex toys he wanted yet. This was going to be his first time using a dildo, though it definitely wouldn’t be the first time that coach Stevenson’s hole had been fucked.
Going back to the mirror with the bottle of lube, Mark turned his ass in view and spread his cheeks. Between those two honey dew sized cheeks was healthy pink skin and a beautifully clean hole. Putting a beefy finger inside with no lube confirmed his suspicion. His new ass was perfectly clean inside and out. Did coach prep his hole this morning in hopes that a student would break his headswap rule and that he’d get to switch neck down with them? Did he prep his hole every morning hoping to get fucked? These questions only served to further turn on the young man.
Mark removed his finger and got a handful of lube. He put some on and in his new hole and the remainder on the dildo. He then brought the office chair over to the mirror. He reclined it back a bit and then locked it into place with its mechanism.
Mark sat down into the chair and lifted his large legs up, using the arms of the chair as sort of stirrups and once again revealing his new hole. He took the tip of the thick dildo to his rose bud and braced for pain as he began to penetrate himself.. only the pain didn’t come. Coach probably used this dildo on the regular so his hole was perfectly used to the impressive girth. In fact, it felt the same as only putting a couple fingers into his former hole. In other words, the perfect amount of girth for his new body.
Mark fucked himself while staring at his new huge body in the mirror. He started to call out, “Oh coach Stevenson, fuck my ass!” The coach’s face came to mind. Mark had never fantasized about the coach before, but having a masturbation session in his body was the single most sexy thing that’s ever happened to Mark. He orgasmed picturing the coach’s masculine five o’clock shadowed face. It was more cum than he’d ever produced in his original body. He stuck some of it in his mouth and ate it like honey.
Mark looked at the clock in the office, first period was almost over! He had to hurry up and clean up. Luckily Mr. Stevenson kept cleaning stuff for this exact situation. Once the office was back in its original state, he put the cheetah print bikini briefs back on. It was a shame to hide these under a pair of pants but he had to. Mark had just gotten fully dressed when the coach came back into the office.
“Alright Mark, you’re free to go to your next class,” said coach Stevenson.
It would’ve been hard to concentrate with coach still dressed in only Julian’s tighty whities, but luckily Mark had just cum and had his post nut clarity.
“But what about my body?” Mark asked.
“You’re gonna wait till tomorrow to get this back, otherwise I’ll tell the principal how you didn’t register this neck down body before taking it to school. Now if you’ll excuse me, I have a new pussy to tame,” said coach, turning his new shapely ass in briefs towards Mark.
“Okay coach but if I may say so, this is one sexy body you put me in,” said Mark, still appreciating the orgasm he just had in his now very mature body.
Mr. Stevenson raised an eyebrow, turned on, and said, “I’ll allow it. Now get that big fat butt to your next class.” He gave Mark a spank as he sent him off, making Mark’s ass jiggle.