“Aw man, you always beat me!”

“What can I say?” the babysitter said smugly, “You might get this good in 20 years, if you practice.”

“Hmph!” Leafy said, scooting the controller away from her, and folding her hooves.

“Can we play something *fun* maybe?” asked Mark, the colt laying on his back and staring at the ceiling, “Racing games are boring!”

“Huh, well I know something you both would like,” the sitter said, tossing his controller over to the game set, where the demo carts were racing again. “You can’t tell your parents though, because it’s totally not allowed.”

“They also said video games weren’t allowed,” Leafy ventured warily, “But we never told about those.”

“Yeah, you foals are great,” said the sitter, ruffling her mane with a hoof.

“Eehee, stop!” she squealed in unconvincing amusement.

“Okay, gather around,” he said, as the colt and filly scrambled over to stand before the lanky stallion, “Here’s the reason it’s not allowed. Have you ever wondered why you two have different private parts?”

“Oh, because it’s our... what about our private parts?” Mark said skeptically.

“Well, you’ve got a penis, right?” the sitter asked. Mark nodded, and the sitter continued, “Well Leafy doesn’t. She’s probably never even been able to touch one before. What she has between her legs is a vagina, which is way different from a penis.”

“Y-yeah, so?” Mark asked.

Turning to Leafy, the sitter said, “And Mark doesn’t even know about what’s between your legs. You think it’d be nice of you to show him what a filly’s like down there?”

“Okay that makes sense,” Leafy said smartly, “But when does it get really fun?”

“In a sec, don’t worry,” he assured her. Turning to Mark, he said, “So Mark, you need to lay on your back, so you can show Leafy what a penis is like. You’re gonna let her play with your sheathe and... you know, whatever she wants.” Looking at Leafy, he said, “Be careful though. A colt’s very sensitive down there, especially his balls. Have you ever felt balls before?”

“...no,” Leafy said quietly, giving Mark a thoughtful look.

“They’re little soft things between his legs,” the sitter said, “You can push at them with your nose if you want to feel what Mark’s are like. But you know, whatever you want. That’s the game pretty much, is you each let each other touch, in whatever way you’re curious about.”

Mark rolled on his back, forehooves curled, looking up at the sitter saying, “Like this?”

“Yep!” he said, then gave Leafy a nudge that way, saying, “Go ahead. See what his sheath feels like. You’ll be able to find his balls down there too. And don’t worry I am absolutely not gonna tell on you, so don’t worry. Haven’t you ever been curious what a colt is like down there?”

“Yyyeah?” Leafy said, looking longingly at Mark’s soft little sheath, “So... so this is okay with you?” she asked Mark.

“Only if I get to do it too,” Mark insisted, “But you can go first.”

“...huh,” Leafy said, sauntering up to the colt and looking between his legs.

“Spread your hind legs,” the sitter advised, “So she can really get at your junk down here.”

Mark did, and Leafy’s experimental nuzzle pulled back surprised. “Oh, it’s... realy soft!”

“That didn’t feel bad,” Mark assured her. “If you wanna mess with my penis go ahead.”

Leafy went to nuzzling again, declaring in bemused surprise, “Why does it smell um... spicy?”

“I dunno,” Mark said, “Is that bad?”

“No, it’s... good,” Leafy said with strange feelings clearly rising up in her. Her tongue slipped out to lever up the colt’s ball sack, whereupon she said, “Oh wow, these are your balls?”

“Y-yeah,” he admitted, looking with some trepidation at the filly between his legs, “I dunno what they’re for, but yeah, I... have them. You don’t have any balls?”

“You wanna see?” Leafy said looking up to Mark’s eyes with an eager smile.

“Hold on there,” the sitter cautioned in mock astonishment, “I think something’s going on with his sheathe. You should rub it down there a little, see what happens when you do that to a colt.”

Leafy’s inexpert hoofing of the colt’s sheath was offset by the fact that Mark hadn’t ever had anypony touch him there before. “Oh, that feels...” Mark said bemusedly, then lightly humped up against Leafy’s arm. “I don’t know why I’m...” his butt cheeks clenched again thrusting him into her hoof briefly, “...doing that. It’s uh... good?”

“Your penis is coming out!” Leafy exclaimed, as the colt’s dark shaft started to extend out from his sheath.

“I don’t need to pee, though!” the colt protested.

“It’s fine,” the sitter said dismissively, “You won’t be peeing for quite a while. It’s okay Leafy, you can touch his penis if you want, or even... lick it.”

“Lick it?!” she exclaimed, looking at the thing with a hunger rising in her young breast. “I... really?” she asked, looking questioningly at Mark.

“He’ll get to lick you, so it’s fair,” the sitter insisted, “It’ll feel good too. Okay Mark?”

“Yeah, o-okay,” Mark said, licking his lips, and looking down at the filly staring at his shaft poking out of him.

Her exploratory lick made Mark hump up into the air again. “Sorry! I didn’t mean to...” he forced his butt to relax, saying, “It just felt *really* ...good, I guess?”

“I’m gonna try licking it more,” Leafy said eagerly. She did, to Mark’s befuddlement, until she exclaimed, “It’s getting bigger!”

“It... it is!” Mark agreed uncertainly.

Leafy went back to licking, whereupon Mark declared, “I can’t stop making it... bigger, if you keep licking it like that! Unh, it’s getting so... big and... uhn!”

“I think that’s as big as he can get,” the sitter said to Leafy’s engaged tongue sliding all along the colt’s erect shaft. She craned back to look at it, as the sitter added, “A colt’s penis gets like this when he’s ready to have something called sex with a filly. His penis is really big and hard, and good at pushing into things. Here, stand up Mark, so she can see how it just sorta hangs between your legs.”

Mark did, looking at it himself, then bit his lip, as involuntary muscles flexed, slapping it against his belly. “Oh, that’s—...” he said uncertainly.

“Well Leafy, how about let Mark have his turn now?” the sitter suggested, “Just turn your butt his way and lift your tail. He can get at your fillyhood that way.”

“O-okay,” she said a little uncertainly, the filly turning and lifting her short young tail.

“What do you think’s gonna happen when you lick *her* private parts?” the sitter asked Mark as the colt curiously approached the filly’s green furred hindquarters.

“A-am *I* gonna get a big penis too?” Leafy asked anxiously.

“Sort of,” the sitter said, “You have a vagina, not a penis. It’s a... place that goes inside you, with the entrance at your slit. Go on, give it a lick, Mark.”

“Oh!” the filly squeaked when he did, startling at the feeling.

“Lick firmly, not lightly,” the sitter instructed, “You’re not trying to tickle her. You’re trying to massage her fillyhood with your tongue.”

Leafy whimpered a little, but caught herself saying, “No no it’s just weird it feels... good. Your tongue’s really... wow.”

“You’re getting thicker and deeper right now,” the sitter told Leafy, striding around in front of her, where his thick stallionhood was hanging loosely between his legs. “That’s what your boner is. You have a vagina all the way up into your belly, that’s waking up right now, just like Mark’s penis. Can you feel it?”

“I... um... he’s p-pushing his tongue in, I... think,” the filly said, staring forward dazedly, “I feel really... melty?”

“That’s your vagina growing wet and slippery,” the sitter explained, “It makes it really easy for Mark to slide into you there.

“O-oh,” she said distractedly.

“Smell my penis,” he instructed, standing over her and crouching just enough to lay his half erect phallus across the bridge of her muzzle, “It’ll make you even wetter.”

“It’s *really*... spicy,” the filly said, her inhalation more like panting than smelling as she slightly rocked her vision obscured by stallion dick. She snorted, standing there stiffly, growling, “I feel really... melty in my... vagina.”

“Alright, Mark,” the stallion said, not moving one inch from where his dick was right now. “Now you need to hug her hips against yours. Just hook your forelegs over her hips and pull yourself against her.”

“Okay, I... okay?” Mark said, struggling up and hugging her hips to his, “Now what?”

“Stick your penis into her vagina, and push it all the way into her belly.”

“What?!” the filly squawked, rearing up under the sitter, who hastily retreated back at the astonished filly, saying, “It’s way too big!”

“You think he’s big now?” the sitter said in amusement, “One day your vagina’s gonna be big enough for *this.”* Slapping his dick against his belly for emphasis, that only made the filly even more owl eyed, saying, “But yours is... is... huge!”

“Mares are pretty amazing,” the sitter agreed, “That’s what you’re gonna grow into, is an amazing mare, who can just sit on a monster like this, until she’s got him balls deep.”

“S...so he *can* put it into me?” Leafy asked uncertainly.

“Yyup,” the sitter said, “That’s what’s the fun part about sex. Now get your penis inside her already, Mark.”

“I... it’s under her belly though!” Mark protested.

“So flex it!” the sitter retorted, “Like this!” he demonstrated with his definite erection now, slapping his belly. “You did it before. Just lift it up to hook it into her slit, and push it deep into her as you can.

“One good push I bet,” he added to the flustered Leafy, “And he’ll slide schhhoop right up into you.”

“If you insist,” she said, blushing embarassedly, “I just didn’t know I was that big ins...”

“Feels good, doesn’t it?” he asked, as the filly trailed to silence at her own penetration.

“It... ow—it—it’s... *really* stretching me,” she said, teeth tensely clenched.

“It’s... really hot inside. A-are you okay, Leafy?” Mark said.

“She’s fine, just a little new at sex,” the sitter assured him. “Just stay inside her for a while, Leafy you take deep breaths and imagine yourself relaxing and expanding around him. And hey, it might be tight, but his whole penis is inside you, huh?”

“It... I *really* feel it,” she said, looking back at the colt mounted on her rump and then back to the stallion, “It... okay.” She took a few deep breaths then.

“You feel *really* good Leafy,” Mark assured her in amazement, “You’re really hot, and really wet.

“I feel you in there!” Leafy retorted, “You’re all big and... and hot and into me!” Her voice got a little emotional as she said achingly, “I don’t want you to ever leave~...”

“Don’t worry, part of him’s gonna stay in there for quite some time,” the sitter assured her. “You’re just gonna be walking around tomorrow, and Mark’s semen’ll still be right there inside your belly.”

“His semen?” Leafy asked in vague curiosity.

“I’ll show you,” the sitter said, squatting down to stroke his own shaft in the crook of his hoof right in front of her, well in front of them both. “I’ll show you what... Mark is gonna do inside you.”

The foals watched in fascination, as the stallion stroked himself to stiff erection. Well, in some sense. “I... I really like it when I slide in and out!” Mark announced, having apparently discovered thrusting.

“M-me too!” Leafy said, “You keep... pushing it *deep* and stretching—unh...”

“M’gonna show you,” the sitter murmured, hungering for the filly even as the colt began fucking her. “P-please lick me a little,” the sitter said, straddling her again, “I need to feel your tongue on it, just a little.”

The filly actually lifted a hoof and curled it over the stallion’s shaft, and her tongue started trailing along the side with very little hesitation. “Mark you’re... inside me with *this* Mark,” she panted against the stallion’s shaft, “You’re pushing this... big *thing* inside my belly! I... I love it. Ohhnmph,” she moaned, outright nomming on the stallion’s tip, wrapping her mouth around the flat head. Not flat for long though.

The sitter flared, and the filly choked. He pulled back desperately, and slipped out of her mouth for two panting breaths, before flaring again, hard, his penis blooming in size before her, and her colt.

“This is gonna... happen to you,” the sitter said, smacking his own belly with his fucking club, “You’re gonna get *big* inside her,” smack, “And you’re gonna,” smack, “H-here’s what his semen is,” the sitter announced, stroking his own shaft furiously, the tingle rising in him uncontrollably, “Mark’s gonna push it deep into you, and... and this is gonna happen to him. I put it in a mare and... and... oh jeez, Leafy, this is s-semen this is... yes... s-semen!”

The sitter ejaculated hard, semen jetting out of his penis in strong spurts, splattering against his belly, splurting onto the floor, standing there with his bobbing penis throbbing rhythmically, thick ropes of semen erupting out of his flared tip, while the two watched in arousal and amazement.

“He won’t have as much,” the sitter said, as the tenseness started to flow out of him, “But he’s still gonna put semen inside you. His stuff’s... got his cells in it. Part of him is just gonna start squirting inside you, and it’ll stay in you for days. Ponies’ll think you’re just normal, they won’t be able to tell you’re standing there with Mark’s semen inside you. All oozing up in your womb.”

The filly squealed loudly then, “Ah?! What’s—ah!! Hahh! Ha—!” Her pupils narrowed, as her entire body stiffened, mouth hanging open in shock as the colt fought to thrust into her.

“Breathe, Leafy,” the sitter said, and the filly met his eyes and tried, then gave a throaty moan as she sank into orgasm.

As she panted there, tail bobbing where it was turned aside for the colt to penetrate her, the sitter said, “That’s what it feels like for me, Leafy. Every time your vagina squeezes, that’s one spurt of semen for a boy. You can’t stop squeezing around him, and he won’t be able to stop spurting into you.”

“Nnahh,” Leafy said, breath coming slower and deeper as her inner convulsions began to release her.

“Can you feel it, Mark?” the sitter asked, “Building up in you, this tingling that just wants to fill your penis? That’s what’s gonna make you orgasm. Feel that tingling just fill your penis up until you can’t stand it, then you’re gonna flare, and spurt semen into Leafy.”

“I f-feel it...ohh I can just... spurt it inside her?”

“Push it deep and cut loose,” the sitter said with a grin, “Leafy’s gonna love feeling your semen spurting into her.”

“It’s... I... oh...” he panted, breathing tenser and higher with every thrust. Looking back over her shoulder, Leafy said in awe, “It’s happening to you, too!”

“Can you feel his flare, Leafy?”

“Feels so good...” she said in utter ecstasy, “Mark, you’re growing inside me!”

“I... I feel...” he said, staring at her intensely, his whole body tensing up.

“Feels so good, doesn’t it?” she said lovingly, “You can start spurting inside me. My vagina’s all... ready to be filled.”

“I... hahh—!” he tried to say, then just started ejaculating into her.

“That’s it, spurt all your semen into me,” Leafy said serenely, gazing at the orgasming colt hanging onto her round little rump, “Just like him, it keeps coming out of you. I’ll keep every spurt inside me—ooh. Good one! Oh, you’re... it’s okay you can stop spurting, too. I’m already fulla your semen.”

“I... I love your butt,” Mark said emotionally, hugging Leafy against him.

“I love it too,” the filly said, pushing back into his embrace, “Because it’s got *you* inside it.”

“Now I want you to look away from Mark and lift your tail.”

When Leafy did that, the sitter said, “Okay, Mark, you can go see what’s between her legs. Then she can look at your