Soul wasn't sure what to expect as he came over to his best friends Malcore's house one sunny summer afternoon, all he knew was that the son of one of the most powerful mages had gotten his hands on one of his fathers transformation books and promised soul, a third generation mage with little to no power the afternoon of a lifetime.
Being rushed into Malcore's bedroom which frankly, at the best of times had a funky smell the boy played off as spell components when everyone and their uncle knew that he was a diaper wearing sissy, Soul took a seat on Malcore's bed. 
"Ok so..I found a spell I think your SUPER gonna like! It'll turn you into a diaper and then I ca-" Malcore started to say even as soul burst out arguing.
"H-hey! who said I wanna be a diaper!?!" He blurted out, even as he squirmed lots.
"Oh uh.. well I caught you huffing my room the other day so assumed.. I mean.." Malcore's face fell, and tears welled up. "I-I thought I had a spell you'd love! I risked a lot to get this book you know!"
Soul instantly felt bad for A) making malcore feel bad and B) for lying. still, he had to save face..
"Fine..I'll be a stupid diaper..but you BETTER be able to turn me back and no taking a dumb in me!" He huffed, even as his body language screamed 'dump in me! dump in me!'
"oh yeah, there's a reversal spell and everything, I mean, there's a warning butt.." Malcore shrugged.
Before Soul could ask what the warning was, he was frozen in place as Malcore began to chant, and felt himself shrinking down even as he got puffy, till he was a thick, white diaper with his face on the butt of it. 
"Huh..your face was suppose to go on the front." Malcore said, looking over the book and reading, then grinning. "Oh! unless you want me to poop in ya! heh, I was just gonna take a leak!" Malcore laughed but hey, who was he to judge want his friend wanted since he was a willing diaper boy?
Sliding his jeans off Malcore made quick work of taking off his soggy diaper and then paused, tapping his chin. 
"uhh.. it says your gonna experience some of this.. would baby powder be icky for you?" Malcore asked, thinking that he had done the spell so that soul could talk but well, he was a novice.
'Yes! baby powder! use baby powder!' soul mentally screamed, already having all the regrets but well, when his prone diaper form said nothing Malcore just assumed he wanted the full experience.
taping his friend around his hips, Malcore went all starry eyed, marveling at how THICK of a diaper Soul made and just how awesome he felt! He could FEEL his friends lips mashing and smooching his bun, making the silly little diaper boy giggle.
"oh wow! I'm gonna have to do this to you way more often!" He gushed, patting his butt and making soul mash against it.
Soul meanwhile was torn between hating this, he hadn't count on smooching Malcore's smelly but and gushing over this was everything he had ever wanted. 
if Malcore could of seen the rear of his diaper, he would of seen Soul's face go from normal to a anime drool face.
"Ok Uh.. I don't actually hafa poop right now..but the spell book says the longer I leave you as a diaper, the more you'll wanna be one.. sooo.." and as malcore spoke, Soul could hear him flipping though the pages, wondering what the little diaper dork was up to.
while soul had been outed so to speak as a wanna be diaper, he wasn't worried about Malcore blabbing since he could confirm Malcore was nothing more then a diaper boy..at least till he heard the 'AHA!' from malcore.
"Ok..One super bowel moving spell coming up.. this says it's gonna be painful for me so you better be grateful!" Malcore huffed to soul, then giggled as the butt smooches went over time. "O-Ok! I get it! you are!"
casting the spell between giggles, even malcore would be shocked as the effects took hold.
Sure, daddy had made him mess more then once for being a bad boy..but the sudden cramps and then the release that this was..
Malcore howled and cried out, going onto his hands and knees,crying as wave after wave of mush came out of him, his eyes and nose burning as the diaper that was his friend bloated out, but that would be nothing compared to what soul was experiencing. 

If there was one question Soul should of asked before all of this (well ok, there was several) it was would he be able to taste.  Sadly he had his answer and it was a yes. 
the face on the back of the diaper went from drooling to making a grossed out face but soul knew even if malcore wanted to, there was nothing the novice mage could of done to stop himself from filling him out.
worse then the muck, it was the solid mess that followed and pressed against him, pushing him out more but somehow the feeling was almost.. nice? No more then that!
even as Soul filled out and made a comically massive poopie diaper, the face on the back of it went from going all grossed out to drooling and with hearts replacing the eyes as malcore finished up.

Malcore panted, sweat dripping from his brow and shocked to still have bones left after a poopie like that. 
"Soul..you..you ok back there?" Malcore asked and felt a movement in the diaper. Soul was too far away to kiss him directly but was making the mess squish around.
"Heh, GROSS! Ok..I was gonna wear you for awhile but I think I better turn you back." Malcore said, spotting the book where he had dropped it in the middle of his epic dumping.
crawling over, he didn't dare stand less he fall on his butt and the book warned a leak would be bad for soul, Malcore flipped the pages and read the counter spell and waited.
after 40 seconds of nothing he read it again and again, waited, but again nothing.  one last time he tried and then gave a nervous giggle. 
"Uh.. Soul, we might have a problem.."

Soul had been busy living up his dirty diaper dream, embracing it as he knew any second now malcore would turn him back.. then heard the counter spell fail over and over.
'Nooo No no no no no...' Soul whined mentally.
"Sooo Yeah.. that warning? said if the diaper actually loves being a stinky diaper..I can't turn them back.." Malcore said sheepishly. "Likeeee..I had a feeling you'd like this..buttt.." 
'NO! I don't wanna stay a poopie diaper forever!!' soul thought, and tried to will himself to hate what was happening to himself.
"I guess all I can do if you don't wanna turn back is toss you out..or admit to daddy I stole his book and ask him for help." Malcore said and paused, thinking about how MAD his dad would be and shuddered. "Sooo Hey, you like this anyways, so I'm just gonna leave you." he said quickly.
Soul could only scream even as the face remained the same, though whether from desire or just frozen in place as malcore cleaned up, no one would ever know. 
With him just a massive stinky diaper, Malcore now in a clean diaper and his pants and shirt carried him out to the trash can.
"Sooo uh.. I guess this is goodbye. Don't worry, the spell erased memory of you from everyone but me! your parents will never miss you! Umm.. You were..a ok friend I guess.." Malcore said, holding soul over the trash can with one hand, holding his nose with the other.
"look, you really stink, I'm just gonna drop you in and go play Pokemon ok? Bye bye!" Malcore said and with finally wet thud, Soul was left in the trash, the lid replaced.
As soul screamed for malcore to come and get him, the little literal diaper boy had to admit, his final stinky fate was everything he had dreamed of.

the end