Sibling Revelry

When Twilight returned to Ponyville, she didn't go straight home. No, that would have to wait. She had assigned herself an errand that had to be done right away. Strap-on dildos don't buy themselves, after all. Even if they did, she would need to pick it out. It would just be easier if she were to purchase it herself.

Ponyville only had one store that sold adult toys. It was owned and operated by an older mare who personally guaranteed that all products were properly designed for the user's pleasure, and safe to use. Many of her customers were not made aware of this fact, for fear of driving them off. Those that did know about her private product tests were also informed of exactly how dedicated to the craft she was. There was a backroom to this store, with a workshop where you could have a custom dildo made. If you wanted an exact replica of your own cock to find out what your partner was experiencing, this was the place to go.

Twilight entered the building. It was unassuming on the outside, but on the inside, she was met with a rainbow wall of dildos of all different shapes and sizes. It dawned on her that this task may be more daunting than she had initially thought. This would have been much easier if she'd had Shining Armor pick out the right one for himself.

"Can I help you, sweetie?"

Twilight jumped in the air and turned around. She had been startled by the proprietor. "N-no, I'm just... Looking around."

"Looking for anything in particular? If so, I can help you find it."

"No, no, I'll just look around for a bit." Twilight blushed and backed away, tripping over a small stack of shopping baskets.

"Are you alright?" The mare came over and offered her hand to help Twilight up, but Twilight refused it, picking herself up.

"I'm fine, just a little nervous, is all."

"Okay. Well, in that case, I'll let you look around for a bit. If you can't find what you want, let me know, and I'll do what I can."

Twilight nodded and disappeared behind a shelving unit. She had been embarrassed enough today, she wasn't interested in telling this stranger her sexual preferences. She looked around until she found the section with the strap-ons. It took up perhaps half of an aisle. However, even the kinkiest of these didn't come with a butt plug. Most of them didn't even come with a vaginal insert, and none of them were the same size as the one she'd found in her parent's box. She let out an exasperated sigh.

"Having some trouble?"

"It's fine, I just have to pick one and hope for the best."

"If you tell me what you're looking for, I might be able to find it in storage."

"I don't even know if you'd have it."

"Neither do I, until you tell me what it is you want."

Twilight sighed. The mare had a decent point. She exited the aisle and approached the front desk. "I'm looking for a strap-on dildo that has inserts for both the front and back. Do you have anything like that?"

The mare shook her head. "No, but I can have one made by the end of the day, if all goes well. If you like, I can even fit it to your exact shape. Unless, perhaps, you wanted this for a friend to wear?"

Twilight shook her head. "No, no, this is for me."

The owner smiled. "Great. The first thing we need to do is select your inserts. Do you know your size?"

"Size? Aren't they all about the same?"

The mare chuckled. "No, sweetie, they're not." She reached under the desk, pulling out two dildos. they were exactly the same model, but very clearly different sizes. "This one is a size small, it's most often used by stallions who want to start practicing at the easiest level before trying for something bigger. The other is an extra extra large, and is reserved for only the most advanced users. You'd be surprised how much difference an inch makes."

Twilight stared at the difference between them. The small one would be easily concealed in a pocket, if she needed, but the extra extra large had a greater diameter than her forearm, and about the same length. "What does the medium look like?"

The mare fished around under her desk and came up with a medium. "I'd recommend this size to you, I think. I would guess you have experience, based on what you're asking for, but you're also a bit petite. If you'd like to try out the fit, there's a back room." She pointed to a curtain at the back of the room.

"Thanks," smiled Twilight meekly, taking the dildo to the back room. To her surprise, the mare followed her back. "Do you always watch these fittings?"

"I'll also be needing your measurements. If the inserts don't line up properly, it could cause severe discomfort. I'm also the only one with the key to the first aid cabinet, so there's that."

The back room had a chair with stirrups, allowing full access to whoever was sitting on the adjacent stool. As per the mare's instruction, Twilight stripped her boxers off and placed her feet in the stirrups. The mare had washed her hands and put on gloves, goggles, and a mask before sitting down.

"Why all the getup?" asked Twilight, more out of curiosity than offense.

"In case you squirt, I don't want it going in my eye. As for the gloves, I don't want to risk you ending up with a UTI because of me. Rest assured, everything that goes inside of you is sterile and safe. Now, you wanted double inserts?"

Twilight nodded. "Can we try medium for the back and large for the front?"

"Of course." The mare inserted a large, nondescript dildo into Twilight's vagina and a medium into her arse. Both were attached to a handle and lightly jostled to simulate how they would shift while thrusting. "How's that feel?"

Twilight was panting with her tongue out. It felt wonderful. "I'll take it."

"Good," smiled the proprietor. "I'm glad I could help you find what you were looking for. Now, if you'd go pick out the dildos you want, I'll be waiting right here."