The next morning was just another hot day in Ponyville, but Twilight awoke into it a changed mare.  Reading the rest of the book had thrown her off her daily rhythm, so she woke from her bed at mid-morning, hours later than usual.  With Spike still pestering her about if she was okay, she slipped slowly into her bathroom with a mumble and turned on the hot water tap with her mouth.  Heat or none, she had now learned to enjoy her own sweat.

Standing in front of the full-length mirror, Twilight looked at herself and smirked.  Her once well-coiffed mane was now tousled into an explosion of errant purple and pink strands, her coat matted with dried juice from five orgasms.  But she looked upon her appearance with new eyes, recognizing every curve and thin muscle in her small form, remembering all it had accomplished the night before.  And, above all, remembering her goddess within.

She had experienced much joy in her magic studies, for sure, but never anything like this.  For the first time in her life, she not only felt powerful, but aroused by that power, and by the thought of untapped potential.  And when she trotted around to the tub and looked back at the mirror, she could see her pussy glistening with fresh juice, ready for another go.

The room was heavy with steam when Twilight turned off the water and slid into the bath.  As her backside slipped against the steep porcelain curve, the warm water tingled up her body, sending another pleasant shiver from her hooves up to her horn.  She sighed deeply and summoned the white heart-shaped bar of soap to her.  

Where once she had vigorously washed herself, anxious to start the day, today she took her time, starting with a slow slide down the front of her chest where her breasts had risen.  She traced the approximate location of the shapes in slow, gentle circles, forming a figure eight of lather that tickled her purple fur.  Bringing a hoof to her mouth, she could still taste some of her juice from the night before, a sweet, saccharine brew mixed with the familiar musk of her loins.  And as her tongue traced the edge of her hoof and flicked off the edge, her other hoof slipped the soap beneath the waterline, then guided it over her swollen clit.

“Ohhhhh,” Twilight purred as contact was made.

Rubbing the lather into her chest, Twilight’s back arched and she cringed, her body making low squeaking sounds with the inside of the tub.  As her underwater hoof began making clockwise circles on her marehood, she could already feel her hips blossom into a larger shape, feel the breasts rise from beneath the lather, foamy soap bubbles popping as the pony flesh grew and stretched into new shapes.  She was changing much faster than before - practice, after all, had made perfect - and her longer torso was now rising visibly higher from the small tub, putting her purple breasts on full display.  

She had just chanced to look to her right when she saw the door to the bathroom was half-open, Spike stepping back out of view behind it.  But this time, Twilight wasn’t startled.  Instead, she glared over at the door with eyes narrowed.

“Spiiike,” she called calmly.

“I-I’m sorry, Twilight!” said Spike from the other side of the door.  “I was just walking by and—”

“It’s okay, Spike,” she said, turning the rest of her changed body toward the door.  With her breasts pressed against the edge of the tub, she made a come hither gesture with her slender index finger.  “Come here.  I want to show you something.”

“I’d love to, Twilight,” said Spike, “but you know I’ve gotta go meet up with Snips and Snails and we’re going to—AAH!” In a flash, Twilight’s horn glowed, enveloping the dragon in a purple aura that yanked him into the room hard enough to slam the door wide open.  She stopped him a foot over the bathtub as she rolled on her back, then abruptly let him go.  With a loud clap, he landed flat on top of her.  Before he knew it, Spike’s scaly face was buried between her breasts, trying to hang on to her new lathered curves.  

He looked up at her with surprise, a smile creeping into his countenance.  And as they sat, Twilight could feel something move between them, poking her furry chest with greater intensity.  Shaking his head, Spike placed a claw on each breast and pushed himself up.  Twilight moaned under her breath, wincing as she turned her head to the side.

“What’s happening to you, Twilight?,” Spike pleaded, “W-why are you doing this?”

Twilight smirked, leaned forward, and kissed Spike passionately on his lips.  She gently caressed her soapy hands up and down his back, then tugged gently at each spike on the back of his head.  He abruptly pulled back, then slipped on her soapy body and fell into the water between her thighs.  As his short leathery legs splayed outward, Twilight saw that his small pink cock, which prior to then she thought little of, was now three times its original size and hard as a rock.  Spike, suddenly embarrassed, smacked his claws back over his loins, but in his haste did so a little too hard.

“OW!” he yelped, “What was that about?”

“I’ve got a new task for my Number One Assistant,” purred Twilight, her hands slipping to Spike’s lap.  Still confused, Spike stared up at her as she gently pulled his hands away, exposing his angry little member as it stretched out further to meet her touch.  Her slick, soapy, satin-soft right hand then wrapped itself around the shaft, sending a shiver through the dragon’s little body.  “I want you to enjoy this.”  Then she started rubbing him up and down, up and down, slow enough for her to feel every pulsing vein in his rod.

“Unnnnnhhhh, ooh, Twilight,” murmured Spike, his cock filling her hand as blood rushed to his face, “I-wha----ffffuuuhhh, wh-what is this?”  

Almost immediately, Spike could feel his legs begin to grow as well, stretching and thickening along with his cock.  Twilight slowly picked up the pace.  The toes on his clawed feet splayed outward as they crept beneath the water and touched bottom between his caretaker’s legs.  As muscle and sinew bulked out beneath his scales, Spike found himself standing up on their mighty length, making him much taller than before.  There, Spike stood exposed.  Wet, carved muscle stretched his broadening chest many times its original width.

Twilight sat up from the bath, both her arms outstretched, and licked her pony lips.  Her left hand cupped Spike’s throbbing balls that swung freely between his legs, and she leaned forward onto her knees, her breath tickling the tip of his cock.  

Then he felt it.  Her tongue slipped up the underside of his shaft, then flipped the tip.  Spike shuddered, his new lantern jaw pressing into his thick neck as his lengthening tail flopped out of the tub.  Instinctively, his big clawed hands reached for the back of Twilight’s head, which was now looking up at his powerful new body.  With a grin, she closed her eyes, gently tracing the circumference of his glutted tip with her fickle tongue.  Then her mouth widened and she took him completely, his balls thwacking her chin as he slipped down her throat.  

She could feel Spike’s claws dig harder into her scalp, but the pain an afterthought, completely masked by the two fingers of her right hand that were two knuckles into her pussy.  In and out, in and out, and the salty musk of dragon sex filled her mouth, tickling her sensitive tongue as he fucked her mouth.  She could feel his heartbeat, his breath, all of him as never before.  She could feel his whole body throb harder and harder as her hands reached up to knead his leathery ass.  His pace quickened.  She could taste his sex, his desire, his power building within him.

Then, all at once, Spike moaned louder than before and something splashed down Twilight’s throat in one hard pulse.  She swallowed quickly, but no sooner had she tasted his salty goo before Spike’s cock twitched again, unleashing more and more until it filled her mouth completely, puffing out her purple cheeks.  Remembering the book’s advice, Twilight backed out quickly and swallowed it all in one hard gulp, but another stream of cum squirted from his cock and slapped her on the nose, thwacking a glistening line against the right side of her face.

She raised her stroking hand and licked her lips, but when she saw Spike’s body begin to shrink, she took action.

“Oh no you don’t,” she said sternly, grabbing Spike’s cock tightly, “we’re not done yet!”    

Almost instantly, Spike’s lost height returned, and his cock continued to throb in her hands.  She looked up at her toned dragon lover and stood to her feet, her hands rubbing his wanting cock.  He was a head taller than her now, his face darker and much more menacing, so it wasn’t difficult for her to submit to him.  She turned around and presented him with her ass, her long tail still twisting this way and that, wafting the scent of her sex towards him.  

She backed into him as he stepped towards her, both of their forms dripping a mixture of cleanliness and filth into the burdened tub.  His arms wrapped around her middle and she gasped, bulging biceps pushing into her sides as his right claw reached for her left breast.  As he pulled her close, she could feel his cock squeeze between her lubed buttocks, looking for a way inside.  The tip teased the puffed lips of her swollen pussy, and her breath quickened in anticipation of being filled.  For a moment, Spike’s right hand left her embrace, reaching between his legs to guide it in.  From there, instinct took over as he rammed into her once again.  The arm returned, pulling her closer still.  Twilight moaned loud enough to rattle a nearby window.  

He was inside her!  

For a moment, Twilight and Spike’s bodies locked together as her tight insides stretched to accommodate him.  Then he pulled back and drove into her again, her juice splattering all over his balls.  Quickly, his tempo increased.  Twilight grasped a shower rod as Spike fucked her into a frenzy.  With every stroke, her hands slipped down the rod until her body was parallel with the ground, breasts shaking freely, smacking against her curves with every thrust.

She could feel his claws explore all of her, slipping across her soapy fur to her breasts, clamping down on each once again.  Then his digits squeezed down harder until her nipples poked between his hard fingers, talons digging deep into her pony flesh.  She screamed to the uncaring wall from the pain, so she pulled Spike’s right hand down to her clit, stirring it onward toward orgasm.  He was hurting her, but she loved it.

Spike began to grunt in deep, bellowing noises, and he grabbed one of her buttocks with each hand, wrinkling her distinctive cutie marks beneath each grasp.  He fucked her faster still, his head arched back with a long lizard tongue slipping out of his grinning mouth.  It was not long before she felt the throbbing again, but this time she couldn’t tell if it was her or him.  The orgasm snuck up on her this time and she yelped in confused agony, trembling in place along with Spike.  Spike’s cum blasted deep inside her soaking womb and she squirted back, each responding to the other as her body locked onto his.  The cum continued to flow, and both lovers were helpless to stop it.  The mixture trickled out of Twilight’s pussy, making loud dripping sounds into the bath water.

As their juices emptied, the two slowly began to return to their normal forms once more.  Spike’s cock flicked out of her pussy, spurting once more onto her crack as his member retreated back into his small dragon body.  As he slipped back into the tub, Twilight’s front hooves returned, and she stood on all fours in the tub.  Spike slipped over the front of her flank and ended up straddling her back, utterly exhausted.  As they stood, Twilight looked back at Spike, feeling the mixture of their sex floating about her hooves in stinky white swirls.  

Warmed by the afterglow and the encroaching sun, a soaked Twilight summoned a pen and quill from the next room.

“Dear Princess Celestia,” she wrote, “today, I discovered that friendship isn’t the only thing that’s magic. . .”