Rarity leads Scootaloo to her bedroom and places the new changing pad she bought on her bed.

“Come here you big filly, let’s get your diaper changed.” She says as she pats the changing pad.

Scootaloo smiles and climbs onto Rarity’s bed, lying down on the pad Rarity removes Scootaloo’s shorts and plastic panties. She looks at Scootaloo’s very wet and messy diaper and begins to gently rub the diaper’s front.

“Well, you sure do need a diaper change. Had you wet once more, you would have leaked all over into your new shorts for sure, even with the plastic panties. Rarity can see the brownish fluid that had already seeped into Scootaloo’s plastic panties from the over full diaper and knows that another heavy wetting would have been too much even for them.

Scootaloo again smiles.

“I just can’t stop using my diaper Rarity. It feels so good to just let go in it and feel how warm and squishy it gets. I knew I needed a change and that’s why I asked you for one, before I go to Twist’s house.”

“Well, I’m glad that you are aware of how much you use your diaper. As long as you’re staying at my house I’ll be here for you to change you, whenever you have the need. Now let’s get this super stinky one off you, okay?”

“Okay Rarity,” replies Scootaloo.

She proceeds to open Scootaloo’s diaper exposing its contents and Scootaloo’s
erection to her.

“Here Scootaloo, let me show you a new way to enjoy your diapers. It might help you work out some of your extra energy.”

“Um, ok Rarity. What’s that?” She asks.

Gently pushing on Scootaloo’s poop smeared erect penis with the tip of her hoof, Rarity begins to rub it up and down its length, slowly at first, but then with increasing intensity. The warm slimy poop helps to lubricate her hoof and adds to the pleasure Scootaloo begins to feel.

“Wow Rarity, this feels so good! It felt nice before, when it was in my diaper, but this feels even better.”

“I know it does Scoots, I want to show you how to enjoy your poopy diapers as much as you can, and this is one of the best ways there is. Honestly I probably should have shown you how to do this earlier, even before you began to wear diapers.”

Scootaloo begins to breath heavily and close her eyes, and in under a minute she groans and her body shudders and a bit of clear fluid leaks out of her penis and mixes with the poop now covering Rarity’s hoof.

“Oh wow Rarity, that was so cool!” I’ve never felt so good; I’m going to do that every time I use my diapers from now on!

Rarity laughs as she uses a baby wipe on her hoof.

“Oh, I’m sure you will. And I’m sure that you’ll become very good at learning how to make yourself feel good. Perhaps next time I’ll show you how to make yourself feel even better by touching your pussy too.”

“You mean this here?” Scootaloo askes pressing a hoof to the poop smeared pink folds right below her penis.

“Yes, that there. But that can be dealt with later, right now, it’s time to get you into a clean diaper.

After sprinkling her crotch area with baby powder as the last step in the cleaning process Rarity brings up the front of the diaper between Scootaloo’s legs. She then securely fastens the tabs in place. Since Scootaloo had worn the same plastic panties since last night, Rarity goes to her dresser and gets out a fresh pair.

“Here you go my cute big filly, a fresh pair of plastic panties for your diaper. This will help keep you from leaking while at Twist’s house.”

She then pulls the plastic panties, green ones this time, up onto Scootaloo’s diaper as Scootaloo raises her butt so that Rarity can perform the task. She then puts Scootaloo’s new shorts on her and asks her to get up and onto the floor. She then adjusts the shorts to cover her diaper and gently pats Scootaloo’s butt.

“There now, diaper filly, what will you do at Twist’s when you’ve wet yourself? Will you be careful not to pee too much and have your diaper leak? You wouldn’t want to leave a wet mark on her furniture, would you?”

“No Rarity, I won’t do that at all. I’ll be careful and come home for a change before it gets too wet.”

“Okay then, you’re all set to go play.” Scootaloo hugs Rarity and thanks her for the unexpectedly nice diaper change. She then runs out of Rarity’s room to go to Twist’s house.

Upon arriving, Scootaloo knocks on the door. Within a few seconds she hears a pony approaching and the door opens.

“Hi Scootaloo, come on in.”

She walks in and sees Cookie, Twist’s mom. She says hello to her as the two fillies race off to Twist’s room. When they get there, Twist shows Scootaloo her new toys and new school supplies for the upcoming year and the two of them settle down on the floor next to Twist’s bed and chat about random things while absently playing with various toys.

Scootaloo wound up being distracted enough by being in her friend’s room that she didn't consider the fact that at times she leaned far forward enough that the top of her disposable diaper would show.

It appeared to Twist that her friend was wearing some very different panties, or something. Twist could also see up Scootaloo’s shorts a bit and saw what she thought was plastic-looking material. She also noted that her friend’s shorts looked stuffed and puffy on her.

‘Is she wearing...a diaper?’ Twist thinks to herself.

‘Why would she be wearing that during the day? Does she get put in diapers at night like I do? I wonder if she would tell me if she did?”

Scootaloo finally notices Twist’s attention on her and not what they are talking about. She becomes a bit self-conscious at first and blushes a little before she brings herself back under control.

Twist doesn’t see any of this and Scootaloo thinks about how she can bring up the subject of his diapers.

“I um, sort of noticed that I can see inside your shorts, I wasn’t looking on purpose, it’s just that sometimes when you moved around, I could see up inside them… It looks like you’re wearing um, a diaper, or something” Twist says hesitantly.

“Well, you’re right, I am wearing a diaper, and plastic panties on over that.” Scootaloo says.

“Wow, I never would have thought that you would be wearing one of those.” Twist holds back on saying ‘as well’ for now.

“What for?”

“I’ve just had some accidents lately… you know, wet pants accidents; so Rarity thinks that diapers will help me until I get through this and regain control.” Scootaloo tries to keep her answer simple as possible and not go into why she was wetting her pants in the first place.

“Um, do you pee in it?”

“Yes, I pee in it.”

“Wow…” Twist says, not sure what else to say. She can’t tell if her friend likes being in her diapers or not, and until she knows one way or another she is too embarrassed to discuss her own diapers with Scootaloo.

“I’m not sure I get it, but if Rarity thinks it will help…” Twist finally adds.

“Its ok, I don’t expect you to understand. I know, fillies our age don’t usually wear diapers, but that doesn’t mean that they can’t. Well, I hope you will keep this a secret between us.”

“Yah, of course.” Twist says and smiles.

She wonders if she can spend more time with Scootaloo in the future and see if her friend really does like wearing diapers like she herself does.

The two fillies play together and as expected Twist leaves to use the bathroom while Scootaloo pees in her diaper. Though Twist secretly wishes she could be wearing her own diaper during the day. Neither filly speaks about what they are doing to the other so Twist has no idea if Scootaloo needed to pee or if she has done so in her diaper. She’s too hesitant to ask that kind of question for now.

Scootaloo soon feels the need to pee again and this time she lets a little out at a time. She thinks to herself how good she feels when she urinates. She likes the feel of her pee as its works its way through her penis and then out into her diaper. Peeing, to Scootaloo, is just a wonderful feeling. The fillies play for about an hour and Scootaloo decides that she better leave soon and get her diaper changed. She’s been wetting it off and on for several hours now and can feel its fullness.

“I’ve had a great time playing, but I need to be going. I’d like to come back sometime and play more,”

“Really? I’ve had a good time too. I’d like you to come back soon,” replies Twist, happy that she might have a chance to see her friend again, and maybe ask more about her diapers.

“Thanks Twist, and you’re invited to my house anytime too, once my mom gets back in a few days.”

“Cool, I’ll be sure to ask my mom when I can come over.”

Scootaloo and Twist get up and walk out of Sweetie’s room to the front of the house. There, they meet Cookie again and Scootaloo says goodbye and thanks her for letting her come over, she thanks Scootaloo for coming over in turn and for being such a good friend of Twist. Scootaloo leaves the house and begins her walk home.

While walking home, she begins to feel the urgent need to poop. She stops walking and looks down at her diapered crotch. She contemplates what to do; should she hold it or should she use her diaper? What will it feel like to walk home in a poopy diaper? As she looks around at her diaper, her bowels again moved their contents and Scootaloo decided that why wait. She would need a diaper change eventually anyway. Rarity had said that she could use her diaper as her toilet anytime she wanted.

Convincing herself that it is okay to do so, Scootaloo relaxes her bottom and her bowels respond and she begins to poop herself. She grunts and pushes even more and poop begins to quickly fill her diaper. It feels warm and soft on her bottom and makes her diaper bulge out even more. The bulge is already large and it expands further as more poop finds its way into her diaper. Scootaloo likes what she’s doing. She likes the feel of pooping herself out in public and how her diaper is bulging with it. She begins walking again and continues pooping herself. She pushes and pushes to empty her bowels and relieve herself of the pressure on her bottom. After about a half block, she stops again and has a final push. She’s convinced that she’s pooped all she’s going to this time. She again places her hooves on both her front and backside to feel her bulging diaper. As she does this, her bladder signals that it again needs to be relieved and she gladly lets go and further pees herself. She feels the warmth of her urine flow into her already soaked diaper. She likes this feeling too. She likes that her diaper is holding everything inside and that it feels so big. She rubs her bottom and feels her poop move around against her butt and over her pussy and balls.

“Wow.” Scootaloo says to herself.

‘This is just so cool. I’ve wet and pooped my diaper right outside and it feels so good. My diaper feels great being so full, this is just the best. Maybe I am like a baby after all, I just love my diapers so much.’

Convincing herself that she’s okay with these feelings, Scootaloo begins walking the rest of the way home. Her poop finds ways to move around with her steps. Scootaloo can tell that she’s walking with her back legs spread a bit wider than usual but she just smiles to herself.

“I’ve just pooped my diapers; I am a big diaper filly and I like it.”

As she walks, she smells the first scent of her poopy diaper. She likes how she smells and feels good with what she’s done in her diapers.

Rarity is in the family room when she comes in the front door.

“Hi Scootaloo. Come here and tell me all about your day at Twist’s house,” she says.

Scootaloo walks to her and Rarity sees that Scootaloo is smiling from ear to ear.

“Well she must have had a great time judging from her expression,” Rarity says to herself. As Scootaloo hugs her, Rarity smells her poopy diaper but decides not to bring it up just yet, she wants to hear what Scootaloo has to say.

“So then, what did you say to her about your diapers?”

“She saw them when I sat down and then asked me about them. I said that I was having accidents wetting my pants and that you felt that diapers would help me through this. I said that other ponies sometimes wear diapers too. We didn't talk about them for very long.”

“Well that’s right Scootaloo, you explained yourself well. I’m glad that you are okay with Twist knowing that you wear diapers. We both know that you’re not a baby even though you smell like one right now.”

Scootaloo again smiles at Rarity, knowing that she too smelled her poopy diaper.

“I can see that they make you very happy, which is good. So, when did you poop yourself?”

“Oh it was when I was walking home. I felt the urge to go and I thought about it and that you said that my diaper is my toilet, so I did it. I just pooped my diaper.”

“Well that’s right, you did just fine. Let’s go and I’ll change you.”

“Oh Rarity, I’d like to stay in this diaper for a while. It feels really good all full and everything,” says Scootaloo.

“Well let’s see how messy you are; stand here and let me check you out.”

Scootaloo come over and Rarity unzips her shorts and drops them down to the floor. Rarity feels her diapered bottom and front making sure to squish the big soft bulge of poop in the back several times.

“Well, your diaper is not quite yet full of pee but you sure do have a large load of poop in it. How many times did you wet yourself?”

“Twice at Twist’s house, and some more after I pooped myself walking home.”

“Well, you can stay in this diaper until you wet it some more. Then I am going to change you. I don’t want you to get any nasty rash on your bottom but you seem so excited having filled your diaper that you can stay in it. Okay?”

“Thanks Rarity!”

“You be sure to tell me when you wet yourself again, and get a towel from the bathroom to sit on. I don’t want any stains on the furniture or carpet. Okay?”

“Will do Rarity, thanks again, I love you!” says Scootaloo as she scampers off to her room, via a stop in the bathroom for a towel.

Rarity smiles to herself as the diapered filly she’s been caring for this last week disappears down the hall.

“That filly certainly is happy in diapers, wet and messy ones at that.” She says while shaking her head in amusement.