The great swap. The great swap was not a well known effect, but it did impact enough people to make news on the internet, just not enough for the general public eye to be aware of it. 
The swaps occurred randomly, someone falling asleep as their normal selves would wake up in the body of another and have to get used to living like them, as there was no simple way to reverse the process. While many tried to claim they had swapped bodies and were not used to the role of the person they were now in, the problem was people took advantage of that in order to get 'retrained' or to get governmental aid, so people that did swap, what few there were, were merely told to just 'adapt and deal with it' which was unfortunate for those that transformed.

A young female fox anthro awoke with a stretch and a yawn. She grabbed the covers to try to keep herself warm, and then immediately realized something was wrong. She opened up her eyes and looked down to see a female body lying in bed, her own female body wearing black pajamas. She glanced over to the side and saw an array of weapons aligned on the wall, and then a large television in front of her currently in standby mode.
"Well... crapbaskets." She mumbled. She pulled herself out of bed, opened up the door, and went to a much, much larger room, a room that had to be custom made by the very construction worker there. "Emily! Wake up! It happened to us!"

The door to the other room was small but the inside of the room was massive, more than 100 feet in size with a doorway to the outside, but not to the rest of the house. Building the room alone was extremely expensive, even for a construction worker. In that room was a fox taur lying on multiple beds, measuring that 150 feet in length and lying on his side. His eyes fluttered open to see the huge brown door in front of him. He rushed to sit up, but smacked his head up against the ceiling "Ack! Ty! What the heck?"

"I guess the swap hit us." 'Ty' groaned. Why did he have to swap bodies with his sister? "I can't do any construction work like this." Sometimes, on rare occasions, swaps could just change jobs and then get back to a normal routine of sorts, but in this case it wasn't feasible. Ty was now in the body of Emily, a regular sized fox anthro. Ty was famous for his construction work with his massive size! That would only mean one thing... "I guess this means you have to go to my work and uh... I have to do yours."

Emily shook her head, rather she shook the head of the body she was now in that was the massive 150 foot Ty's body. "Gah! I mean, your job is pathetically easy but I can tell you that you can never do mine! You know what it takes to kill a person? Can you even do interrogation? No, you're not cut out for that!"

Ty opened her mouth to give a different response, but then she heard Emily. "Wait. Easy? Oh come on! You have no idea what my job is like! It's a massive amount of lifting and carrying and putting things in the right place very high up in the air! You couldn't handle it! Your job is the easy one! How do you kill someone? Simple!" Ty raised her thumb in the air and pointed an index finger forward, as if mimicking a weapon. "Pew pew." She blew on her finger, as if blowing on a hot used gun. "There. Enemy down. Next target."

Emily scoffed. She stood up and got out of Ty's massive bed. In Ty's body she wore blue pajamas that miraculously covered Ty's massive body from neck down to his many paws. "Alright then, you know what? I'm going to go do your job just to prove to you how easy it is and you do mine. It'll be like one of those cliche tropes where we swap jobs and lives, because we literally have to now!" Emily reached down to undo her clothing, but paused. "How about a little privacy while I get dressed?"

"It's MY body." Ty rolled his eyes. He had to get used to being in Emily's body, just like Emily would have to get used to his. She would see that being in the body of a macro taur would not be nearly that easy. He walked into her room and paused. "Guh... let's get this day over with. Hardest part of this day is going to be changing clothes for me."

After a few hours of doing things Ty wished not to describe, he began his work day in Emily's body with a briefcase full of weaponry that would have made the cartoon coyote that always chased the roadrunner jealous. His job was simple, find a target and eliminate them, or in some cases, incapacitate them. He already had a massive amount of paperwork pointing out where this person was, and they started off their day at a local cafe that Ty drove to. Ty's driving was a little reckless, on one part that he never really drove when he was a macro taur, and on another part that he had only two legs instead of four, which really threw him off. He had to drive Emily's black small car slowly to get to his destination, but he got there before lunch. The target was a horse, a brown horse that had been a potential known suspect for causing swapping bodies, although for what reason was unknown. The idea was to take her out and nobody else should swap bodies! Or, at the very least, the amount would be reduced. Ty parked the car in a parking garage and stood on the other side of the street where he saw the female horse drinking a cup of coffee in the cafe and working on something on their computer. 'Perfect. So she's one of those kinds of people. She'll be in there for hours, but this should only take minutes if she's sitting still! How hard could this be?' Ty thought with a sly smirk.
Ty's outfit on Emily's body was a black outfit that almost appeared to be made of latex. He stood out in the open and pulled out Emily's first choice of weapon, a blowdart. 'This might shatter the glass, but Emily breaks things ALL the time during her line of work she tells me.' Ty put the blowdart to his lips and took a deep breath in preparation to fire the dart already loaded in the bamboo weapon. As he inhaled, the dart shot backwards into his mouth, and he wound up swallowing the small thing.

Ty's mouth stayed puffed. His body quickly turned green and he began sweating. "Oh... sh..." Before he could even finish his sentence, he collapsed.

Ty awoke some time later to find that the horse was gone. What time was it? He glanced down at his watch and noticed he had been out for a good hour. He then looked from side to side to notice that not a single person helped him. 'Real friendly city to help someone who's unconscious. God. Wasn't that blow dart supposed to kill whoever it went into?' He recalled Emily talking about how much intense training she had to go through. Did some of that training require becoming immune to poison darts? Whatever the case was, he still had a job to do! Okay, maybe Emily's job was a little harder than he first thought, but he wasn't going to stop. He checked on the horse's schedule and noticed that they included a GPS in her car and that it was on the move. "Oh, I know a shortcut there. You're going down, pony!"

A few hours later, Ty stood on top of a cliff with his car parked haphazardly onto the side. Below the cliff was a road that led out of town, and Ty saw from the GPS on the pony's car and the pony's schedule that she would be leaving town. Yes, this would be her chance to destroy the pony and prove how easy Emily's job really was! Ty stood next to a massive boulder and smiled as he looked down at the road below, a good 100 foot drop if he had to guess. "Alright, there's your black car. Now, according to my calculations, all I have to do is push this boulder off the cliff and it'll crush you like a bug!"

Ty glanced down as he watched the black car. He wasn't the best at math when it came to small numbers, but a quick guesstimate told him if he dropped it now, it should at least block off the road and at the most, crush the car. He put his hands up to the boulder with all of his might and pushed!
...and pushed.
...and pushed.
Ty quickly realized one fatal flaw with his plan. His normal giant size was naturally gifted with superb strength. He didn't have to try to pick up anything that was small. He could lift cars, people, things that were small and took little to move, and things around his own size when he was a macro were only buildings which were easy to destroy. This boulder was, however, one hundred percent rock.

"Of course." Ty mumbled before he watched the car casually drive by as if nothing happened. He felt as if he were in a silly cartoon, but even cartoon characters had the strength to push a boulder. He checked his map to see where his target was going, and he had one last chance to catch her before she went out of state. This time, he was going to be ready for her! He pressed a button and signaled for a helicopter ride so he could get to his destination before his target could. He had to prepare something else for them, and they were going to be in for a surprise!

A few hours later...

Ty felt strange with these weird time skips, but they made for a productive day. The sun was setting and he had one last chance to destroy this person! He had set up a few landmines placed on the road and all he had to do was press the button on his remote to detonate them. He placed them right outside the tunnel, the point of which he would no longer have a chance to assassinate that horse. 'If I were a coyote in this desert, I would have painted the tunnel to look fake.' He thought to himself as he waited just outside of view behind an edged corner. He poked his head out from it to see when that car would be arriving, and he saw it already on its way.

Ty quickly went back behind the rocks and, just as he heard the car zoom to the tunnel, he pressed the button to detonate the land mines. He had placed enough to destroy the road nearby and then some, hopefully destroying the car and his target in the process! However, as he pressed the button, nothing happened! The car zoomed on by. Ty poked his head out, pressed the button again, and went back behind the rocks only for nothing to happen again.

Now, Ty was getting furious. He could no longer get his target and he was undoubtedly out all that money. He stomped to the road where he placed the mines, able to see the silver antennae sticking up from above the road. While standing on top of the landmines, he was about to press the remote, but his finger stopped just short of the red button.
"WHAT AM I DOING?!"
Ty let out a sigh and walked off from the road. He tossed the remote behind him and, just as he was a good distance away, with a massive boom the landmines blew up. He wished he could say he was surprised. Okay, maybe being an assassin was trickier than he thought.
"I just hope Emily is having a better day than me."

Emily wished she was having a better time. While getting to the construction site was easy during the day, once she arrived, she looked over the massive building they were constructing. "Uh." She commented once she arrived at the site, seeing massive steel beams so high up, yet at her new size, she would have never fit into the building. "So do I get an orange vest or something?" She asked, genuinely curious. "And where's all the equipment?" Rather than bulldozers, she saw massive shovel-like objects made of steel that might fit her new size as shoes. She saw no cranes to pick equipment up, elevators, or ladders for that matter. She asked a foreman, a fox foreman who was about the size she once was and he had a hard hat and orange vest on. At least, Emily was pretty sure he was the foreman. It was hard to tell when everyone was that tiny.

"Where's the... oh for crying out loud." The fox anthro shouted from below. "Did you and Ty REALLY... okay look, I'm going to keep things simple for you. Your job is to pick up people and equipment as needed and then put them where they need to go, alright? We're all equipped with hard hats and parachutes for a good reason but Ty was a good enough worker to never need them, so hopefully we don't need them around YOU!"

Emily quickly straightened all four of her legs. She stood up and began to quickly rush her hand to her forehead to make a salute, as she did, she immediately knocked one of the columns on the steel beam tower down without even realizing it until after her salute finished. "Yes sir!"

The worker facepalmed seeing Emily already destroy one of the beams. While it didn't cause the entire building to collapse, it bent into a strange V shape. "Just... just put me on your back and do what I tell you."

Emily did just as the worker instructed. At first things were going fine. She'd pick up people and set them up on the platforms, she'd carry supplies around, she thought this was super easy! As she was working, she stepped forward and heard an awful crunch noise. She glanced down in fear that she stepped on a person, only to realize she stepped on the portapotty. "Ack!" Thankfully the bathroom was empty, but she stepped on it hard enough to break the roof. Still, stepping on something so disgusting caused her to backtrack and, unfortunately for her, she was not used to having four legs. The worker held onto Emily's back while she stepped back onto a stack of steel pipes which were big enough for her to not only step on and cause a crash, but spill forward and cause her to lose her balance as she tried to maintain her footing while the round pipes spilled all underneath her. She grabbed the construction tower out of sheer instinct to try to maintain her balance, but as her body fell, she took the beams, and the entire tower they were building along with it, crashing down with a heap of dust and deployed parachutes. Emily pulled herself up with a blush on her face, and very annoyed construction workers surrounding her, and that was putting it politely.
"So um..." She rubbed the back of her head. She turned to watch the other construction worker get off her back. "Am I going to get fired for this?"

Both Emily and Ty went home late at night, both sighed frustratingly as they walked into their home. 
While Ty should have been happy to be so small that he could fit wherever he wanted, he was now without a job, unable to assassinate his target successfully and messing up so many times. Emily really did have it hard. All he had to do was be careful about where he stepped and he'd be fine. Construction was easy when he just had to lift people, and he could do it with no problem! Emily on the other hand needed clever thinking and good dexterity, and that was putting it politely.

Emily on the other hand found being in Ty's body she had to behave like a gentle giant. Along the way to work she hadn't paid much attention to what she stepped on, but only along the way home did she notice how easy it was to smash cars, bikes, and if she dared stomp because she was mad, and she was a little furious on her way home, she'd make craters with her paws as imprints on the ground. She got home and she wanted to scream, but she swore the entire state would hear her body. "Ugh! Why are you so clumsy!" She called out in a normal tone, which even for Ty was a big booming voice for the size of the body.

Ty heard Emily's voice. Rather, he heard his voice come out of his body that Emily had. Ty walked into the room that was once his and saw the rather upset Emily. "You lost your job too huh?" He said with a frown. "Yeah, I didn't realize how tricky it is to off a person."

"It's easy once you learn, especially that target. She was very open and..." Emily paused. "Okay, I'd say it was easy, but clearly you couldn't do it. I can see your face is green. Did you uh... accidentally have some poison?"

Ty slowly nodded. "I uh... inhaled before I exhaled. Glad you got that immunity when you did."

Emily sighed. "Okay, they are working on a way to switch bodies back. I'm not sure how long they'll take, maybe never within our lifetimes, but if we're going to be stuck in each other's bodies, then before we start applying for new jobs, I'll teach you how to be you, and you teach me how to be me. At least, in our bodies. I can't exactly be a stealthy assassin in this body, and you can't be a strong construction worker in yours."

Ty smiled faintly up at Emily. She had a point. They were still them, but in their new bodies, it was going to take some adjusting. "Okay, that sounds good. Worse case scenario, I could become a story writer and you could advertise it for me. You do get around the city easily. Would you support a patreon and join a discord if I started one?"

Emily rolled her eyes and lightly bonked Ty's head. "Maybe. Okay, let's get started teaching each other about our lives. Maybe if we're lucky, we can land those jobs back and do better next time."

Ty's lips spread wider with that smile. "Sounds like a plan."
