Rarity looked through her dresses at the Carousel Boutique. Something was wrong, but she couldn't quite figure out what it was. Did Sweetie Belle move things around? Almost everything was where it should be, but there was something wrong. She looked at one of the racks of dresses and noticed that one of the hangers were naked. She always removed hangers after a pony purchased a dress, so there was only one thing she could think of. Someone stole her dress!
She partially blamed herself for not setting up an anti-thievery spell. All unicorns who own a business are familiar with that spell, and she used it every day. It prevented unicorn magic from picking up an item requiring ponies to enter the shop. Ponies were less likely to steal items if there was a high risk of getting caught. Of course, it didn't completely eliminate theft. The Pegasi and Earth Ponies had their share of thieves, too.
She decided to not open the shop today and instead went to Sugar Cube Corners. She waved to a few ponies on her way there. When she got there, she saw Pinkie running around frantically through the window. She walked in to see if Pinkie was OK, but the pink mare kept muttering to herself. She said something about not taking the entire cake.
“Pinkie Pie, are you alright?” Rarity asked.
“Yes indeedy!” Pinkie replied. She gave a fake smile.
Rarity knew her friend well enough to see right through her. “What happened here?”
“Some pony, I don't know who, took a bite out of one of the cakes,” Pinkie explained. She remembered Rarity stealing some cake once. “Was it you?” Of course, Fluttershy and Rainbow Dash also took a bite of the cake at that time, and only one pony took a bite of this cake.
“No, In fact, one of my dresses has been stolen!” Rarity told Pinkie.
Pinkie Pie gasped then shouted, “We need to stop that thief!” She got an idea. “Rarity, you should use your generosity magic to make the thief give everything back!”
Rarity looked at Pinkie in confusion. “I don't have 'generosity magic', Pinkie. Wherever did you come up with that?”
“You know, when you blast baddies with your light!” Pinkie reminded her.
Rarity sighed, “That was from the elements of harmony, which we gave away awhile back.”
“How did we defeat Tirek?” Pinkie asked.
Rarity rolled her eyes. “We used the Rainbow Powers, and I am certain that we can't just isolate one and use it.” Could they? They never tried it. What would even happen if only one pony used the Rainbow Powers?
“Oh.” Was Pinkie's only response.
“Perhaps we can find this thief together,” Rarity suggested.
Pinkie replied, “Okidokiloki!” with a wide grin on her face.
Rarity explained, “The plan is to set a trap for the thief. We are going to make something look easy to snatch, but not so easy that they will know it is a trap.”
“Great idea!” Pinkie agreed. “I can can make several cupcakes look average and one cupcake look perfect!”
“That could work!” Rarity said excitedly.
They also agreed to spy on the cupcakes to see if anypony steals one. Rarity helped Pinkie with baking the cupcakes that are to be used for the trap. After the decorations where finished, they rearranged it so that removing a cupcakes wasn't obvious. A good thief would never take anything when it's easy to get caught.
After everything was set up, they hid and waited. Ponies came and went, but no one stole a cupcake. Finally, everything slowed down. Rarity noticed a cupcake being levitated into a saddle bag. She recognized the fushia star that matched Twilight's cutie mark. Twilight was the thief?
Twilight left without a second thought, and Rarity followed her. She made sure to keep a distance between herself and Twilight so she wouldn't get caught. She didn't expect Twilight to be a thief. Twilight went inside the castle, and Rarity went in right behind her.
“Hello, Rarity,” Twilight greeted.
“Go to the dining room, now!” Rarity said in an angry tone. That was her favorite room in the castle, mostly because she decorated it.
Twilight nodded and turned towards the dining room. She sat on one of the chairs. “What's going on?”
“dump out everything in your saddle bag!” Rarity commanded.
Twilight did what she was told and gasped after her saddle bag was empty. “Rarity, I really don't know how these got here!” Twilight explained.
“Are you sure?” Rarity asked.
Twilight nodded confirming it. She wasn't feigning her shock. She was really shocked. She stole the items, but she didn't realize it.
“Twilight, do you have kleptomania?” Rarity asked. If Twilight stole things without even realizing it, maybe she was a klepomaniac.
“I don't know, but other ponies asked that same question,” Twilight admitted.
“I may not be a doctor, but I want to help you,” Rarity told Twilight. “You can't steal things from other ponies. I understand that you are unaware of it, but I think we can deal with that issue.”
“How will you do that?” Twilight asked.
Rarity levitated a spray bottle from her saddle bag and answered, “I am going to use this. When I spray you with this, it will sting for a second, but it will help you get your urges under control.”
“Are you sure this will work,” Twilight questioned.
Rarity nodded. “I am certain. Are you willing to try this?”
Twilight replied, “Yes! I will do anything!”
Rarity noticed a cupcake being levitated towards Twilight, so she sprayed her with the bottle.
“Ouch!” Twilight screamed. The pain went away instantly, but she still remembered it. A cupcake fell on the table in front of her. She realized that she was going to steal it.
Rarity and Twilight agreed to go to the bookstore. Twilight knew that it was the perfect place to get her kleptomania under control. She wanted Rarity's method to work, even though it was painful. She didn't care about that. In fact, the pain was meant to discourage theft.
When they got to the bookstore, they walked around together. Twilight looked at the books like she was a filly in a candy shop. She wanted to look through the books, but she wasn't sure if Rarity knew if she was stealing or not. She vaguely noticed a tingling sensation in her horn, but it disappeared as she felt her side burning. She made a mental note to pay attention to her horn.
The next three days where similar. Twilight and Rarity went to various places to test Twilight's control. The first day was difficult. Twilight barely knew she was stealing until it was too late. On the second day, she was aware, but she still stole various items, most of which lacked value. On the third day, she has more control, but she stole two paint brushes at an art store.
The fourth day was different. Rarity wanted to think Twilight was ready to go at it alone, but she worried that Twilight would go back to her old ways after knowing that no one was there to spray her. It hasn't been very long. Rarity made her decision, "Twilight, I will no longer stay by your side every minute, and we will no longer do these tests. There is one thing I need you to do, though. If you have the urge to steal, holds your breath for ten seconds. It should discourage you."
Twilight looked at the ground, "I don't know if I'm ready."
"I don't know if you are either," Rarity admitted, "but as long as you want this to stop, you will get there. I can only help you do much. Ultimately, you make the decision if you want to change or not."
Twilight smiled with determination, "You're right. I can do this! No! I will do this!"
Rarity wrapped her front hooves around Twilight for a hug, "With that attitude, you are sure to get through this."