Day giggled and darted forward, flaring her wings to get just enough space to glide. With expert precision, she came to a stop right before her best friend and licked her lips.

“Wait…” Lily said as she pulled out the dildo. Her hips continued to buck involuntary. “I… you told me Professor Study was going to see if she could trigger your…”

Day felt a flush of pride. Without further ado, she yanked off her white top, revealing the two tan breasts beneath. She hadn’t fit into her bra after Study had helped her to the next stage.

“Oh my goodness!” Lily cried, her eyes glowing with happiness. “You’re… you’re…”

Day settled down on her knees, reached up a hand to each tit and gently squeezed. The pleasure forced a little moan from her lips. She felt her wingboners go up even as liquid trickled down her front.

“You’re a full mare now!” Lily squeed. “Oh my goodness! I… this is amazing! We’ve talked about it for so long… wow, you’re so much bigger than me now! And your ass! Damn girl! You could get any stallion or mare you want like that!”

Day smiled, blushing hotly despite being totally on display for her best friend.

“Mmm… in fact… I think you’re going to… ahhh… get one right now!”

Day’s eyes went wide as Lily’s wings flapped a single time and the other filly pounced on her. Day yelped as she went crashing back to the ground, but a quick move by Lily made her hit her head against Lily’s arms instead of the ground.

Then Lily’s lips were on hers and the world vanished. Day’s body arched into the kiss and she moaned, her body lighting up light a hearth. Lily capitalized on the chance and slipped her tongue into Day’s eager mouth. Day fenced with her best friend as wings and hands rubbed all over Day’s body.

She knew Lily was talented, but it had been months since she’d managed to get Day completely naked while atop her.

Finally, Lily broke off the kiss and began to nibble down Day’s muzzle toward her neck.

“But… your… your toy…” she breathed as Lily’s pink hands traced Day’s tits.

“Mmmm,” Lily murmured. “I can always cum to that anytime I want.” Her fingers kneaded Day’s rapidly-filling breasts. “But it’s not every day your best friend becomes a full mare!”

“But… with… you on… top…”

Lily pulled back and stared Day in the eye. Day’s entire body bucked at the sight of her best friend’s pink-coat, golden mane, gorgeous wings and raging eyes.

“I’m going to make myself cum just by drinking directly from you…”

Day’s mouth hung open.

“Mmmm…” Lily mumbled to herself. “In fact… I want to make sure you don’t get in the way of that…”

In a flash of wings and fur, Lily moved with the speed a Wonderbolt. A few seconds later, Day let out an agonized groan of pleasure as she tried to lift her wrists up… but they were cuffed together by soft fabric bound to the floor.

“Pine Mesa gave them to me,” Lily Valley whispered. “They’ll only release their hold after both the wearer and the pony who put them on cum.”

“Oh… Lily…” Day moaned. “I… I don’t think I can… I can handle this…”

“You’re right!” Lily smirked. “I just remembered you mentioned Study Break was teaching you something else…”

Day’s eyes went wide. Not from fear or anything like that. It wasn’t that she couldn’t handle being trapped. It was that she couldn’t handle how freaking hot it made her.

“Yes!” Lily cried. “Did she finish teaching you how to be a…” Lily paused and licked her lips.

Day felt her tits filling like balloons and realized she was one of those mares… the ones who could be totally full just by being turned on enough. And her best friend knew all of her triggers.

“How to be a…”

Day whimpered, her hips bucking. It felt like the time Strong Load had teased her with his stallionhood at Winter Formal, always pulling out between every stroke. She needed to be filled. She needed to be filled with those two words.

The fact that it was her best friend who had total control instead of her professor made it all the better.

“That’s it!” Lily cried. “How to be a good filly!”

Day’s eyes went wide… and she went wild. It was only because of the unicorn magic that she didn’t completely tear apart her ‘bindings.’ She cried Lily’s name as she came with only two words.

Then Lily shifted position and buried her head against Day’s tit. A second or two later, eager lips wrapped around her nipple and Lily gave an experimental suck.

Day shuddered, still in the throws of an orgasm… then she let go. Instantly, her milk gushed like a torrent into Lily Valley’s eager mouth. Lily moaned and shoved her naked body against Day’s.

She had a strange flashback… to Study Break sucking on a cock hungrily. It bursting like her tits were doing right now…

Then the thought faded as Lily Valley lifted her head. Her face was coated with glistening white milk. She licked her lips and made a heady little sound of ecstasy.

Then Lily shoved her tongue into Day’s mouth. Day bucked again as Lily’s leg slipped between Day’s two legs. Instinctively, she began grinding herself against Lily’s deliciously soft and sweaty fur. Lily groaned at the sense of it. Day had enough presence of mind to know Lily almost broke down and shoved Day’s leg into Lily’s sex, but the other pegasus stopped herself.

Instead, she pulled back. Day stayed with her, their tongues swirling until Day’s binding kept her from meeting Lily’s lips. Day let out a desperate whimper of need, willing to do anything just to make the wonderful feelings continue.

“You’re such a wonderful,” Lily licked her lips. “Submissive…”

Day gasped again, her eyes going wide as the words drilled straight through her brain, down through her spine and into her sex.

“Good…”

Day panted. Her tits were almost twin fountains of wonderful white milk. Her eyes latched onto Lily like a drowning pony would to a life preserver. The entire world faded save for Lily’s lips.

Then Lily leaned down to kiss Day’s right ear ever so softly. “Filly…”

“Aaaaah! Lily!” Day screamed as her body thrashed and bucked and spasmed and convulsed. The words hit her sex as if Lily had just shoved a dildo up into her all the way and turned it to overdrive.

Instantly, Lily dove for Day’s other tit. She drank greedily, her own hips bucking, her tail flying everywhere, her wings flared out to maximum. Day went crosseyed from pleasure, her mind wandering to all the things Study had promised… no… not promised.

Study hadn’t told her anything she hadn’t already known. Day Dreamer had already known she’d do every one of those things Study had described.

Lily’s suction doubled and Day let out a piercing scream. The sound seemed to drive Lily to greater heights from her dancing ass, so Day didn’t stop even as the pleasure threatened to fry her brain.

“Oh Lily… don’t stop Lily… please don’t stop…”

Lily moaned around Day’s tit. Milk was everywhere. The scent of horny mares filled the air. Lily’s gorgeous mane filled her vision for a second as the other mare twisted.

“Lily… Lily… make me a good filly…” Day groaned, her chest thrashing as much as her hips. “Make me a good… a good filly… drain me please! Drain me, PLEASE!”

Lily’s convulsions increased. Day licked her lips, still tasting her own milk on them from where Lily had kissed her. How many times had Day kissed Lily after suckling from her? Now… she could finally taste herself.

She tasted amazing.

“Good fillys make their… their friends cum…” Day murmured. “Good fillys give milk and make their friends cum hard…”

Lily let out a desperate whimper, her hips going absolutely mad with need. Lily’s hands gripped Day’s shoulders in two vise grips, just shy of bruising.

“I wanna be a good filly…” Day whispered. “I wanna make you cum… make you cum… with… with… aaahh… with my….”

Lily and Day reached a perfect point of synchronicity.

“Please… make me a good filly… and cum from my… my… my… aaaaaaahhhhhhhhh!”

Milk flew as Lily threw her head back and screamed. Day arched her back and screamed at the sheer joy of saying those wonderful words, her sex slamming into Lily’s own. Purely by instinct, the two fillies ground their pussies together. Day’s eyes rolled as her body went into some sort of pleasure seizure. Her wings twitched and flared and flicked everywhere, completely beyond her control. Somehow, Day knew all of this… and didn’t care.

Author's Note

So much milky fun~! These two just can't stop, can they?! I wonder what they'll get up to next~! Heeeee!!!

If you see a mistake, lemme know by PM so I can get it all fixed!