"So, you wanna be big?"
Jagger had willingly submitted himself to Charlie's captivation.  The year was now 2042, and the Stretney was trying new things on this intriguing Sunday evening.  A recent cuddle session with a certain large tiger had intrigued him.  "I do."  The Stretney had put on the odd pound or two with each new birthday and holiday, but he was ready for more.
"Good!" Charlie's blue eyes were as captivating as ever — almost hypnotic. "What are you feeling right now?"
"Hunger..." Jagger spoke, his belly letting loose with a hunger pang like he had never known.
One Chinese-style buffet later, and Jagger had to temporarily undo his belt.  "It was a dirty trick, taking me to my favorite restaurant chain..."  The bearish fellow placed a paw on the top of his bulging stomach.  He was already past the point in his life where he worried what others would think of seeing him overeat.  Most of all, Jagger was just glad there was enough non-meat products to satisfy his hunger.
"Yeah, I'm full of those.  Not much has changed." Charlie then let out a victory belch, his navel almost slipping free of his blue shirt while his shorts could split with one wrong move.  Still, he tested them by leaning forward, a fist under his chin, elbow on the table. "Now, as your coach, I'm obliged to not call myself that too much, but I WILL be leading by example!" And with that, the fat creature slowly stood up and beckoned Jagger to squeeze out of the booth as well, as the night was young, and the ice cream machine was lonely.
20 minutes later, and Jagger finally felt like a true bear for the first time in his life. "I could very well sleep for an entire day..." he managed to get out between breaths.
Later that night, Charlie treated his friend to a belly-massage, both of the creatures in their underwear.  It had been a while since Jagger had been treated treated like this by his provocative friend, though he was not complaining in the slightest.
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     The next morning, Charlie served up quite the feast of pancakes, pulling out a chair for Jagger as he saw him enter the kitchen.  "Morning, king!  Breakfast is served.  Were these chairs always this rickety...?"
"No." Jagger smirked, the chair complaining once it met the creature's furry rear, tufts of fur poking through the holes in his underwear.
"Heh.  It's never too early to go all-in, and I've always found it the most helpful to not stop once you start... until you gotta, of course." With his 'serious face,' on, Charlie began to steadily demolish his own stack of pancakes — not too fast, and almost with something similar to grace.  It already made sense to Jagger, as he barely ever paused during a meal except to sip a drink.  The stomach is its own special piece of art, and it has ways of stretching in particular ways.  While laying on the couch, Jagger received a surprise belly-knead from Finley, who had found a newly stuffed pillow.
Later in the day after a walk, Charlie led Jagger to the newly-adapted workout room, picking up some dumbbells for some bicep curls.  Jagger did the same, and next came push-ups.  Jagger was surprised to see his friend capable of such things, but the Stretney struggled to copy him. "Hey, don't give up!  I bet you'll be doin' tons of these by the end of the week."
Jagger did not believe his friend, but he continued his workout by following instructions.  He still had his innate strength on his side, able to do some things better than Charlie could.  After this, a protein shake with extra ingredients was in order.  "And if it ever gets boring, just switch up the flavor!" Charlie said, determined to make sure Jagger would look forward to such shakes every day.  The Stretney downed most of the prepared shake in under a minute, letting out a ferocious burp afterward.  "That is good... What all did you put in it?"  Charlie just put a finger to Jagger's lips and belly-bumped with him, paws wandering to love handles, rump, chest...
A shower was in order after this, followed by a burrito or two.  Jagger did have one client today, and his own belly got in the way quite a bit, causing him to apologize.  Charlie convinced him later that it was just part of the package, and Jagger accepted this with a warm smile.
Later in the evening, Charlie and Jagger prepared a large amount of salmon, and Jagger was encouraged to use a bit more oil than usual.  The two could barely keep their paws off each other's bellies, but somehow, dinner prep managed to finish, and the only thing left to do was eat — as for the dishes, they could wait until tomorrow, as Charlie had a different type of massage in mind.  Finley escaped to where it was most safe: the couch.
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     Charlie's coaching became a standard in Jagger's life as the weeks went on.  Jagger became able to do push-ups several times per week while still racking up the pounds... much to his scale's dismay.  The sabercat was also bulking up, sporting bigger biceps: a perfect pair of new things for the Stretney to nuzzle.  Each week, the two would inform each other about their own gains, and although it never became a condition, most talks ended up with extended cuddles.
Later in the year, Jagger — 50 pounds of bulk heavier — invited Morton over for a few weeks.  Although Morton's appearance was more on the muscular side despite his large belly's overhang, the two discovered that they now weighed the same. "Dude, you transformed into one hell of a bear!" And it was true: even Jagger's new shirt did not entirely contain his doughy belly.  He gave a flex and smirk, showing that muscle was indeed hiding underneath everything.  Morton was drawn to this with large eyes.  "Dude, you're such a bear, and you seem more confident, too!"
"You could say that." Jagger said, followed by a smack to Morton's rear as the Stretney suggested that the tiger should sit down for food.  The kitchen was oozing with the aroma of familiar food with the addition of food specifically prepared for the Stretney pescatarian.  Charlie finally stepped out of the shower, strutting around naked after drying off.  While he did not realize Morton had arrived already, no one complained about the sabercat's current appearance, and his huge belly hid nearly all of his bits anyway.  Finley opened one eye from her rest, promptly shutting it moments later.
As the hours went on, Charlie eventually put on clothes, tales were shared between the three beasts, compliments were given, and bellies expanded.  Morton groaned and belched before rolling over to the sofa (which he did not realize was a futon in disguise) for a food coma.  Jagger stepped over to offer an extra pillow for Morton, and then the bloated tiger found himself receiving a heavenly belly-massage.  "Oof... gentle, please.  Feels like I'm gonna pop..." and he was not joking, as his belly button looked rather taut around his bulging gut.  The pacified look in his eyes suggested his appreciation before he fully fell asleep.   Meanwhile, Charlie began washing dishes, though Jagger had something else in mind.
Led by the paw, Charlie was escorted to the bedroom.  "I have this problem, coach..." Jagger began to speak, eyes darting down to Charlie's paws. "I have this particular ache in my belly from overeating.  Anything you recommend?"  And with a snicker, Charlie soon gave his friend a belly-rub he soon would not forget.
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