Two canines meet together inside a giant tent like structure. One of them being a tall 10foot white malamute with red facial markings. The male full of thick meaty muscles from his wide neck all the way down to his full calves. As he stands looking, his gaze is met by a shorter 7foot and 3 inch blue and white malamute. This fella having a much wider and fatter build with a belly that rounds out at the top and spreads on the bottom being thick and soft.

"So you sure you want to do this Nex," questions the fatter moot.

"I said I did, right?"

They each hold out a emerald stone with cryptic markings covering them. As they extend there arm the stones begin to glow and shine brighter and brighter. Filling the insides of the tent with the green hue pouring from the open seems and bottom  lining of the tent. Soon a swirl forms and wraps quicker and creates more strands as it whirls around the two pups. A strong current being created as their fur fluffs and sways to the whims of it. 

Soon the stones lift from each paw as they glow even brighter. Cracks form into the etched markings. Getting deeper and deeper the emeralds break and continue to break smaller and smaller. Becoming two shimmering piles of green dust. As the current picks up the dust piles go to the opposite owners and infuses inside of them. Each canine letting out a huge gasp and stumbling back as they were hit. Looking back at each other again, the chords of green whipping around them start to close in more and more. Eventually, pushing the them together until they are smashed up against one another. Arc having his muzzle shoved on Nex's thick round pecs. The whirl of green grows stronger once more as the two pass out from all the pressure and fall to the floor.

A good few hours later, Nex wakes up and starts to lift himself from the ground. He grunts and groans. Lifting his paw, his eye catches it and stops. Seeing that its not his normal strong digits but something more thick and puffy. He brings it to his muzzle looking it over and moving it around.

"Wha.... did it work...."

Bringing his paw down and rubbing over his pecs only to be meet with pillow like soft mounds. Cupping and lifting them he chuckles as he immediately feels what must be his huge belly as it rest in his lap. A smile and chuckles sound from the malamute.

"It did work!"

Turning his head he see's Arc realizing all his changes. Him now being a muscle head.

"Told ya it would happen. We weight swapped!"

Arc getting up as he flexes those beefy muscles. His stature making them look a bit fuller and wider than the taller pup did. The two rub and feel on each other as there members stir and Arc grabs his and strokes on it while Nex pants and moans lifting up his belly and wobbling it.

"Damn dude, for being a tall guy your body really knows how to keep shape. Think with all that fat on you but nothing really sags. That's fucking hot as hell."

Hearing that compliment it makes the newly fat moot blush as he grabs at his soft belly hang and holds it up revealing his fat thick dick throbs and ooze out his pre. Seeing that prize, Arc reaches with his free paw and tugs on it. Sending pleasure through his partners body as he shudders and shoots out a wad.

"Oh fuck.... I can feel more than just my cock down there now.... my pad it really thick now...."

"That's what's called a fupa bud and it is quite large....," says the short malamute.

Pressing his paw into your fupa as he takes long strong pumps feeling your cock throb and pulse heavily. Arc wagging his own thick wang as pre slings against your belly as he taps over it.

"How about I take this a fuck those nice hefty moobs of yours. You've always been partial to those, right?"

Nex blushes and nods, "I-I'm more... into.. p-pecs... but yes... fuck them...."

Tugging and pulling on the hot sweaty dick having Nex go to his knees as the muscular pup pushes his fat shaft between those soft thick moobs and rubs them against it as he growls and rumbles. Starting to rick his hips as he fucks letting his dick head rub on your muzzle smearing his pre around it. Grunts and pants fill the area as Nex takes the fat cock head in his muzzle and drools over it as he feeds on the pre spilling from that piss slit and into his already huge belly only adding more to it.

"Thats right.... let's just enjoy ourselves for now....."

Continues to fuck his friends mouth as he stuffs more of his rod down and into his throat as he moves forward pressing his thick thighs against that soft fat frame. Grunting and moaning as he rubs the back of your head and grins.

"Damn, I really was a fatass wasn't I...."

Holding the back of his head with his paw and bringing more of his shaft down til he hilts himself all the way in feeling the fat pups hot breath wave against his crotch as he shudders and rumbles.

"God damn that feels so good hun.... I'm about to cream in you...."

Hearing those words Nex whines and whimpers paying those ears back and buries his snout on that crotch smelling all that thick musk. Arc just growls followed by moaning and clamping down on your head as he funnels all his cream into his friends throat and down to that already impressive belly. Feeling it bloat and push against his thighs more and more. The extra pressure causing Nex to groan and grunt loudly as his eyes move around in his head.

"Oh shit yes! That was perfect...."

Just before pulling off the cum filled canine blew on his under belly and fupa covering it with his thick semen as he stays there a little dumbfounded as he slowly reaches up and rubs on his belly and belches.

"Y-yes.... it was... v-very good...., "stammers Nex.

"Glad you think so hun. You just look fucking amazing right now."

Nex blushes as he slowly wakes from his stupor.

"You look amazing as well Arc. You look like a fucking wall being shorter than I am carrying all that weight. Gotta say though, I'm ready for us to start phase two tomorrow. I do enjoy all this heavy fat but gotta make it even bigger and fuller."

The two admire each others new physique once more til returning back to there homes.

As the next day comes, they met up and plan out everything. Within weeks, Nex shows Arc all the proper and best workout routines while the same happened with Arc helping Nex on eating and knowing just how to retain all that girth and heft. Soon weeks, rolled into months as the two finish up a normal gym workout and lumber into the shower.

"Fuck us! Right?"

Looking over and seeing one another, both males who once swapped body images now have the near identical shape. There shoulders wide and round like perfect mounds with there arms sporting massive boulder biceps. There lower regions supported by fucking red wood like thighs and calves. Nex having focused more on his pecs and making them swell in to massive melons as his nipple hang down sporting huge nobs with milk leaking out. Wearing a shirt with the bottom ripped off that reads, "MOOT HULK". Arc spending most of his time on his ass with it being a wide load and super round and bouncy. Even him wearing a pair of briefs that read, "Super Bottom". Both males still carrying around a massive solid belly that would but a buffet out in mere hours.

"Damn right fuck us," exclaims Nex as he flexes.

Noticing all the gym goers at the time staring as some begin to jerk and others run off embarrassed by themselves. This no longer a shocker to either male as they reach over and begin to fondle each other as there muscles bounce and ripple from the slightest touch or movement. There super bloated beach ball sized nuts swagger and sway with there huge hyper cock rods.

"I'm really glad you agreed to do this with me Arc....."

The shorter malamute blushes and licks on his nipple sucking on it. Within moments the taller pup was hammering away on the shorter guy as the building was filled with there sounds and noises.