RWBY: Dragon's Heart

They soon appeared within the Underworld. Instead of looking otherworldly, it matched the human world, even having a moon. This was due to having been altered by the Four Great Satans, even going so far as to create a fake moon with demonic power.

It was night, and the full moon was in the sky. Yang was taken back by the sight of it, having been used to Remnant's shattered moon. Yin pat her back and took a cursory look around.

They had ended up on a massive cliffside. At the very end of the cliff was a facility. Like one would see in the human world. Shia looked up and paused.

"This looks.. Normal?" Shia muttered.

Yin placed her hand on Yang's shoulder and gestured to the land in front of them.

"Welcome to the Underworld. A land of Devils, Grim Reapers, Fallen Angels and.. other races." Yin explained.

"I always thought the Underworld would be more gloomy.. With lakes of fire." Shia wondered aloud.

"What she said. There any Grimm here?" Yang looked at Yin inquisitively.

"No. Grimm are mostly unique to Remnant. Each world has a number of different creatures plaguing it. This one has a massive variety. Not even Devils are all bad here." Yin explained.

Shia nodded her head and added, "Mn! In my world, we have dangerous monsters. Then there were those cyborgs in the Menagerie dungeon."

Yang seemed to get even more interested, making a fist and smirking.

"You gotta bring me along too. I can access the doors with my symbol right?" Yin instantly felt the need to steer her away from going without her, but stopped herself before she opened her mouth.

She wouldn't be around Yang all the time. And trying to limit her options to grow strong didn't sit well with her either.

"...Yeah. Maybe later you can find them. For now, we should see what this facility is all about." Yin diverted her attention to the facility before them.

Though as they walked, she observed Yang's heart once more. It was accumulating more mana from the atmosphere, but it wasn't as potent as the lower floors in the Orcus dungeon, so the transfornation would take a little time.

"Halt! You trespass on Naberius clan territory. State your intentions!" Two devil guards stationed outside the faacility approached them, the older one speaking.

"Well, that was easy.." Yin remarked, looking at the facility ahead with an almost befuddled expression.

"Yeah! We really came out at a convenient location huh?" Shia chimed in with a small snicker.

"Yeah, seriously. So, how do you guys operate..? You just knock them out or..?" Yang asked, immediately alerting the two guards into caution.

Not that it mattered. They were low class Devils working under a madman from the branch family of the Naberius house.

"Oh, no. We kill them. These guys take in kids, solely to experiment on them. In pursuit of power." Yin clarified, catching the older guard by the neck before he had a chance to fire off his devil magic at her.

Yang furrowed her brows. She wasn't used to killing. But she always had a feeling Yin was, due to her being raised in a bandit's camp. Not wanting to be outdone, she moved and intercepted the other guard before he could flee, smashing her fist into his back.

*CRUNCH!*

And successfully destroying his metal armor, along with his spine. Yang didn't hold back, seeing as these were devils.

"Ah, see? It's easy. I kind of expected you to struggle with it more though, to be honest." Yin stated, closing her fist and crushing the neck of the Devil in her hand.

"Um..." Yang muttered in disbelief.

"I didn't think he'd die.. I thought he was stronger..? He didn't even have aura." Yang replied, looking a little guilty.

Shia felt a pang in her chest and looked away.

"S-So cute.." Yin suppressed the upward turning of her lips after hearing Shia's whispers.

Tossing the body away, she wrapped her arm around Yang, pulling her in a half-hug.

"Auras and Semblances are unique to our universe, sis. Don't feel bad. These guys-" Yang shook her head at Yin's words.

"Oh, no no. I'm not Ruby. I learned Huntsmen and Huntresses do kill dangerous and insidious people. I just felt guilty because he didn't even have a chance.." Yang coughed awkwardly.

"Well here's hoping there's some stronger Devils inside then eh? Oh, make sure to keep an eye out for two cat girls too. We're here to rescue them, after all." Yin stated, urging the two to follow after her as she proceeded toward the facility.

'Cat girls? For some reason.. I feel a little threatened now.' Shia felt a shiver of premonition make its way up her spine.

She'd look into the future, but now wasn't the time. Either way, the two girls were supposedly kids, no? What kind of threat could they even pose?

-Naberius Compound-

"Onee-chan?" Shirone called out, catching the previously absentminded Kuroka's attention.

"What is it, Shirone-nya?" She had felt something in the air for a second. Or so she thought.

"You stopped reading the story. The princesses were all caught by the dragon. Into its nest. See?" Shirone pointed at the picture book she was reading to her.

"Oh, right! Silly me-nya~" Kuroka smiled and began to pick up where she left off.

"The princesses felt as if doom were upon them. The dragon had taken them from their castle with ease and set it ablaze with its mighty flames.. Waaah~ Scary huh-nya?" Kuroka added in some sound effects, putting greater emphasis on the dragon.

"Maybe... the princesses were lonely in the castle. So the dragon saved them." Shirone questioned the picture book.

She was a rather smart ten year old. Kuroka wasn't too shocked to hear her sister questioning the story book. By all means, it was just a regular fantasy book where the dragon takes the two princesses into its cave. Then it gets defeated by a noble prince and they all live happily ever after, except for the rather dead dragon anyway.

It wasn't the first time she'd read it out loud to Shirone. There was nothing to do in their confined room but read anyway. Kuroka stared at the two princesses being taken away by the 'evil' dragon, as if longing for it.

"Why did the dragon take them, Onee-chan?" Shirone looked up at her sister's face and asked.

"Because Dragons like treasures-nya~ The Princesses are like shining gold and jewels to them." Kuroka answered. Though, she didn't truly know if that were the case.

"And why does the Prince come save them?" Shirone asked again.

"Because the Princesses are beautiful women. The Prince wants to be with one.. or both..? Hm.. that's more scandalous than I realized." Kuroka, being a healthy fourteen year old, naturally knew about attraction.

"...Same reason." Shirone muttered.

"Hm? What is-nya?" Kuroka prodded her sister for an answer.

"The Dragon takes them because they're pretty. The Prince does too. Why does the Prince get treated well and the Dragon dies?" That was a harder question to answer.

Kuroka always knew her sister was smart. It was even a source of pride. But her observational skills made it harder to keep the dark truth from her. That she was being used as an experiment by her bastard master. To create a Super Devil. She would need to act soon, if at least to protect Shirone from learning the terrible truth.

"Because.. the Prince loves them." A rather unreliable answer, but she really had no real answer to give. And Shirone counted on her to be a dependable older sister. There couldn't be a question she didn't know the answer to.

Kuroka continued the book, internally sighing to herself.

'Wouldn't it be nice to be saved like that?' She thought to herself before a blaring alarm echoed loudly through the facility.

Both sisters covered their ears, even though the door had muffled some of the noise.

"What's going on.." Shirone groaned before getting used to the loud alarms.

Kuroka rubbed her ears and looked down at the white floor under the crack in the door leading outside. Two of the stationed guards outside their door quickly began to move, away from their room.

"It has to be serious.. To get them to leave like that. A break out? Or a break-in." Kuroka quietly mused to herself.

Either way, it was a golden opportunity. Quickly standing up, she grasped her little sister's hand and stood up.

"Shirone-nya. We should go. We can leave and.. and get ourselves a nice house with plenty of snacks. Way better than here!" Kuroka urged her sister.

"Eh..? But Master Croix.. Wait, snacks..?" Her attention shifted quite quickly at the mention of tasty food.

Kuroka sighed in relief. 'Good to know the power of sweets will still move her.'

"Yeah! Master Croix will be fine here. Let's go!" Kuroka pulled her along, treating it as an adventure while internally dreading getting involved in whatever attack the Naberius was suffering.

Kuroka kicked the door down, using her senjutsu enhanced power to topple the steel door. Pulling Shirone along, she thankfully saw no guards or lab assistants lurking in the halls. She quickly made her way down the white halls, making sure to peek around the first corner she came across.

*FWISH!*

Just in time to see a guard flying and crashing head first through a lab's window. The force carrying him all the way into the back of said lab, where it sounded like every last piece of glass equipment inside shattered at once.

"Okay.. Not there!" Kuroka quickly pulled Shirone along down the opposite end, this time, not seeing any flying guards.

"He went flying far.." Shirone stated idly, even sounding a little amused at the fact.

Kuroka smirked a little. It was kinda funny, given how these guards treated some of the others held here. Even going so far as to set up death matches between subjects deemed as failures. Worse yet, some failures were still quite attractive and given most guards were men...

Kuroka shook her head. All the more reason to get out of this cesspit.

Kuroka and Shirone bounded down another hall. This one filled with the bodies of guards. Thankfully, they weren't ripped apart or anything. But they were definitelty quite dead. Something even Shirone could pick up.

Kuroka felt the sleeve of her yukata gripped tighter by her sister. Despite being bloodless, she understood what happened here. If anything, it made the scene scarier. What kind of people or creatures could do this without really spilling blood? Kuroka wasn't willing to find out.

"Only two more halls-nya~ Don't worry, Shirone." Kuroka said cheerfully, pushing down her own discomfort to raise Shirone's spirits.

Escape looked to be a slam dunk. Until Croix himself was seen outside the back door with a contingent of elite, high ranked Devil guards.

"You two... Did you have anything to do with this!?" Croix, immediately noticed the two and began to nearly foam at the mouth in anger.

It was almost funny, considering how cold and unfeeling the man always carried himself to be.

"Do you think we did all this? I thought us in danger so I came out here." Kuroka deflected the anger and blame with a shrug.

Croix narrowed his eyes. It absolutely must have been thanks to Kuroka. She was his most free, most powerful subject. She must have gotten the word out somehow. To get some chance to get away.

"Anyyyyway~ We're gonna go. Since you can't guarantee our safety anymore-nya~" Kuroka pat her sister's back and began to walk toward the door.

Croix sneered. "No. You're still in my peerage. Which means you'll protect me. Or did you want your sister to be next? I've still got quite a few experiments to run after all."

Kuroka immediately became enraged. It seemed like her plan to kill Croix and free them would have to be enacted anyway. The only issue is that she'd become a fugitive. And they'd likely be split apart. Kuroka looked at her little sister and hardened her heart.

"Very well.." She took one step forward, but then that feeling took hold again. Something in the air.

No, it was nature. Two sources of power had arrived. It was almost intoxicating. Kuroka didn't realize she stopped until she heard a violent 'crack'.

It was a black haired woman with wings, horns and a tail, having landed on Croix and crushing him into the ground. His bones snapped like frail twigs. Then there was another. A golden haired woman with flaming fists, landing on the guard beside the now very dead Croix. Her punch obliterating the elite Devil, along with the ground he stood on. Then, a rabbit girl. Who landed on the other guard, flattening him with her oversized hammer.

"Tch.. I got a weakling." Yin walked off the body, scraping the blood off her boot like it was dirty.

Kuroka realized then and there what the woman in front of her was. It was almost poetic? Coincidental? Comical?

She nearly doubted what her senses were telling her.

Did Dragons come to save them?

[AN: Haven't asked but how do you guys feel about this fic so far?]