Under ordinary circumstances, Sweetie Belle would be mortified by her situation. She was completely filthy, covered from head to paws in dirt and grime. Her newly heightened sense of smell told her that she stank and was in desperate need of a bath, while her new Diamond Dog instincts told her it was okay to be dirty.
Secretly, though she would never admit it to anypony, she kind of enjoyed being covered in dirt.
She must have been tunneling for a while, because she went far enough down into the earth to pop out in one of the many tunnels that snaked their way underneath Ponyville. Rarity had once told her that there was an entire catacomb of tunnels and mines beneath the town. Given Sweetie Belle's new affinity for dirt, she realized that these tunnels were the safest place for her to be.
Slumping against a cave wall, Sweetie Belle took a few moments to examine her new body. She definitely a lot stronger than before, she could tell that much. She had tunneled several hundred meters into the earth, and her massive arms weren't even tired. There were chunks of black dirt stuck beneath her claws, but it was easy to pick them clean thanks to how sharp they were.
Despite there being no actual light in the tunnels, Sweetie Belle found that she wasn't having much trouble seeing. Her new Diamond Dog eyes were designed specifically for night vision, making seeing in the dark an easy feat. Of course, there wasn't a complete absence of light. Gazing down the long tunnel, Sweetie Belle could see torchbugs flittering around, and glowing blue slugs slithering along the ceiling of the cavern.
"I guess this won't be so bad," Sweetie Belle growled to herself, taking in her surroundings, "being a Diamond Dog. At least the caves are nice." She couldn't tell if that was the old Sweetie Belle talking, or her new Diamond Dog self. Either way, she wasn't doing a very good job of convincing herself that everything was going to be fine.
Sweetie Belle sobbed as she started to think about everything she would need to leave behind now. She had to leave her school and her friends. She would have to forget about ever falling in love with Storm Spark now, and she would definitely never be able to see her sister again. Rarity… Rarity had been so angry at her, simply because she was a Diamond Dog! She wasn't even aware that she was attacking Sweetie Belle the whole time!
"I don't need them anyways!" Sweetie Belle asserted, hopping to her hind paws and punching at the cave walls. "I don't need anypony! I don't need anybody!"
Despite her attempts to assert that she didn't need her pony friends, she still felt herself crying and sobbing at the thought of never seeing them again.
"You do know you're not going to dig up any gems by punching a wall?"
The voice had come from seemingly out of nowhere. Sweetie Belle jumped in surprise and whipped around, coming face to face with no less than three Diamond Dog pups. They all seemed to be around her age, and at least two of them were girls. Looking at the wall behind them, Sweetie Belle noticed that there was a hole, freshly dug, in the earthen soil. They must have dug their way over from another tunnel.
The first of the three Diamond Pups reminded Sweetie Belle of a pony named Pipsqueak, and he was about as big as him too. His fur was a dark and creamy white colour, but he had dark brown splotches dotting his body, and one big one over his left eye, both of which were dark brown in colour. His ears, unlike Sweetie Belles, were long and droopy. It hadn't occurred to her that, like regular dogs, Diamond Dogs must come in many different breeds.
The second Diamond Pup, which was clearly a female given the tuft of fur on her head that resembled hair, actually reminded her a lot of Babs Seed, Apple Bloom's cousin. Her fur, however, was entirely dark orange, almost brown in colour, with the long mane of fur on her head being slicked to the right, hanging over her eye. This Diamond Pup had neon-green eyes, which almost seemed to be glowing in the dark.
The third and final Pup, also a female, reminded Sweetie Belle of Apple Bloom. She had creamy yellow fur, stained in a few places with dirt and such, bright orange eyes, and she had a big pink bow tied around her left ear, and eyes that glowed green, just like the other Diamond Dog.
The pony within Sweetie Belle was completely startled by the sudden appearance of three young Diamond Dogs, yet her new instincts guaranteed her that she had nothing to fear from her own kind. A light chill went down her spine as she realized that she thought of herself as being one of them.
"I don't think we've ever seen you around here before," the short male said. "Are you someone new?"
Sweetie Belle twiddled her thumbs for a second, and considered telling them who she really was. "Yeah, I guess you could say that."
"Pleasure to meet you," the brown one said, "my name is Maya."
The one with the bow's ears suddenly perked up, making her bow hop to the side. "I'm Daisy."
"And I'm Killer," the short one said, pointing a thumb at himself proudly. "And together we are--"
All three Diamond Dogs raised their fists in the air and struck a rather dramatic pose. "The Diamond Pups United!" They shouted, in a perfectly rehearsed unison.
Sweetie Belle wanted to fall over onto her back and burst out into laughter. The three young Diamond Pups really had no idea how ridiculous they looked and sounded when they did that. She opened her mouth to make a mention of it, but suddenly realized something that made her blush.
She had done the exact same sort of thing, several times, with Scootaloo and Apple Bloom. The Diamond Pups United, in some strange and wacky way, was a Diamond Dog parallel of the Cutie Mark Crusaders.
"Pretty cool, aren't we?" Maya said, with a jagged-toothed grin.
Sweetie Bell returned the grin and nodded. "Yeah. Pretty cool."
"What about you, new one," Killer continued, hopping forward a few steps and getting a bit too close to Sweetie Belle for comfort, "you got a name, or did your parents hate you?"
Sweetie Belle raised a clawed finger for a second, and was about to tell them her full name, but she decided that it was too pony-ish for a Diamond Dog. "Just call me Sweetie," she told them, cutting off the 'Belle' portion of her name, just to be on the safe side.
Killer and Maya both burst into laughter, but Daisy just smiled. "That's a lovely name," she said, holding her hands behind her back.
"You're not one to talk, Daisy," Maya giggled, "you got saddled with a name just as bad!"
This got an even bigger burst of laughter out of Killer, who was now rolling on ground, holding his sides. "C'mon, guys, stop, I can't," he mumbled, in between fits of laughter, "I can't take anymore. You're all too funny."
"Killer has an overdeveloped sense of humour," Daisy whispered, "try to ignore it as best as you can and you'll be fine."
"Hey hey hey, it's not that bad," Killer growled regaining control of himself. "Now stop me if you heard this one! A Diamond Dog goes to see the doctor and says 'doc, I think I'm going crazy!' and the doctor says 'what makes you say that?' and then the Diamond Dog answers 'I'm Barking mad!"
Neither Maya nor Daisy laughed, but Sweetie Belle couldn't help but giggle lightly.
"See?!" Killer laughed, hopping to his feet. "See? She laughed! I'm funny!"
Rolling her eyes at Killer, Maya went and put a friendly paw on Sweetie Belle's shoulder. "I'm going to go off on a limb and say that you're not from around here, are you? You've probably never been in these tunnels before in your life. And I'm not just saying that because we don't recognize you, coz that happens all the time."
Sweetie Belle shook her head and flattened her ears against her head. She wasn't about to tell them about how she had to leave all of her pony friends behind, given how she wasn't a pony anymore, but she really wanted to. She had a feeling, though, that they would less accepting of her if they knew she had once been a pony. As it were, as strange as everything was getting, it was nice to feel somewhat welcome. And since Diamond Dogs don't get cutie marks, she would never need to worry about being called a blank flank ever again. Maybe this could work out.
"I ran away from home," Sweetie Belle admitted. She really needed to get that off of her chest, considering it felt like it was weighing her down.
As soon as she said it, Daisy and Maya gave her a reassuring hug, as if they understood exactly how she felt. It was actually kind of startling, and it felt like it came out of relatively nowhere. In a way, Sweetie Belle felt like she was back with Scootaloo and Apple Bloom, and she relaxed a little, but in another way, she was nervous; if these Diamond Dogs ever found out that she was actually a pony, they would do to her what they did to Rarity...
"Why don't you come with us to town," Maya suggested.
"We were just on our way to school, as it were," Daisy added, "and we'd be happy to take you with us."
Sweetie Belle thought about this for a second. She would taken to a Diamond Dog town, where she could attend a Diamond Dog school. Considering her options, this wasn't such a bad idea. After all, she was one of them now, so what harm was there in acting like one or living like one? Who knows, she thought, maybe I can learn to like being a Diamond Dog.
"I'd like that a lot," she said, nodding happily.
"Then it's settled!" Killer squealed, jumping into the air, doing a back flip, and landing on his front paws. "Sweetie gets to come with us! The fourth member of the Diamond Pups United!"
"Wait I never agreed to--"
Sweetie Belle didn't have a chance to refuse or deny her membership before Maya and Daisy grabbed her by the hands and started pulling her through the tunnels.